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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/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#include <linux/random.h>
29
30#include <asm/setup.h> /* for COMMAND_LINE_SIZE */
31#include <asm/page.h>
32
33#include "of_private.h"
34
35/*
36 * of_fdt_limit_memory - limit the number of regions in the /memory node
37 * @limit: maximum entries
38 *
39 * Adjust the flattened device tree to have at most 'limit' number of
40 * memory entries in the /memory node. This function may be called
41 * any time after initial_boot_param is set.
42 */
43void __init of_fdt_limit_memory(int limit)
44{
45 int memory;
46 int len;
47 const void *val;
48 int nr_address_cells = OF_ROOT_NODE_ADDR_CELLS_DEFAULT;
49 int nr_size_cells = OF_ROOT_NODE_SIZE_CELLS_DEFAULT;
50 const __be32 *addr_prop;
51 const __be32 *size_prop;
52 int root_offset;
53 int cell_size;
54
55 root_offset = fdt_path_offset(initial_boot_params, "/");
56 if (root_offset < 0)
57 return;
58
59 addr_prop = fdt_getprop(initial_boot_params, root_offset,
60 "#address-cells", NULL);
61 if (addr_prop)
62 nr_address_cells = fdt32_to_cpu(*addr_prop);
63
64 size_prop = fdt_getprop(initial_boot_params, root_offset,
65 "#size-cells", NULL);
66 if (size_prop)
67 nr_size_cells = fdt32_to_cpu(*size_prop);
68
69 cell_size = sizeof(uint32_t)*(nr_address_cells + nr_size_cells);
70
71 memory = fdt_path_offset(initial_boot_params, "/memory");
72 if (memory > 0) {
73 val = fdt_getprop(initial_boot_params, memory, "reg", &len);
74 if (len > limit*cell_size) {
75 len = limit*cell_size;
76 pr_debug("Limiting number of entries to %d\n", limit);
77 fdt_setprop(initial_boot_params, memory, "reg", val,
78 len);
79 }
80 }
81}
82
83static bool of_fdt_device_is_available(const void *blob, unsigned long node)
84{
85 const char *status = fdt_getprop(blob, node, "status", NULL);
86
87 if (!status)
88 return true;
89
90 if (!strcmp(status, "ok") || !strcmp(status, "okay"))
91 return true;
92
93 return false;
94}
95
96static void *unflatten_dt_alloc(void **mem, unsigned long size,
97 unsigned long align)
98{
99 void *res;
100
101 *mem = PTR_ALIGN(*mem, align);
102 res = *mem;
103 *mem += size;
104
105 return res;
106}
107
108static void populate_properties(const void *blob,
109 int offset,
110 void **mem,
111 struct device_node *np,
112 const char *nodename,
113 bool dryrun)
114{
115 struct property *pp, **pprev = NULL;
116 int cur;
117 bool has_name = false;
118
119 pprev = &np->properties;
120 for (cur = fdt_first_property_offset(blob, offset);
121 cur >= 0;
122 cur = fdt_next_property_offset(blob, cur)) {
123 const __be32 *val;
124 const char *pname;
125 u32 sz;
126
127 val = fdt_getprop_by_offset(blob, cur, &pname, &sz);
128 if (!val) {
129 pr_warn("Cannot locate property at 0x%x\n", cur);
130 continue;
131 }
132
133 if (!pname) {
134 pr_warn("Cannot find property name at 0x%x\n", cur);
135 continue;
136 }
137
138 if (!strcmp(pname, "name"))
139 has_name = true;
140
141 pp = unflatten_dt_alloc(mem, sizeof(struct property),
142 __alignof__(struct property));
143 if (dryrun)
144 continue;
145
146 /* We accept flattened tree phandles either in
147 * ePAPR-style "phandle" properties, or the
148 * legacy "linux,phandle" properties. If both
149 * appear and have different values, things
150 * will get weird. Don't do that.
151 */
152 if (!strcmp(pname, "phandle") ||
153 !strcmp(pname, "linux,phandle")) {
154 if (!np->phandle)
155 np->phandle = be32_to_cpup(val);
156 }
157
158 /* And we process the "ibm,phandle" property
159 * used in pSeries dynamic device tree
160 * stuff
161 */
162 if (!strcmp(pname, "ibm,phandle"))
163 np->phandle = be32_to_cpup(val);
164
165 pp->name = (char *)pname;
166 pp->length = sz;
167 pp->value = (__be32 *)val;
168 *pprev = pp;
169 pprev = &pp->next;
170 }
171
172 /* With version 0x10 we may not have the name property,
173 * recreate it here from the unit name if absent
174 */
175 if (!has_name) {
176 const char *p = nodename, *ps = p, *pa = NULL;
177 int len;
178
179 while (*p) {
180 if ((*p) == '@')
181 pa = p;
182 else if ((*p) == '/')
183 ps = p + 1;
184 p++;
185 }
186
187 if (pa < ps)
188 pa = p;
189 len = (pa - ps) + 1;
190 pp = unflatten_dt_alloc(mem, sizeof(struct property) + len,
191 __alignof__(struct property));
192 if (!dryrun) {
193 pp->name = "name";
194 pp->length = len;
195 pp->value = pp + 1;
196 *pprev = pp;
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
205static int populate_node(const void *blob,
206 int offset,
207 void **mem,
208 struct device_node *dad,
209 struct device_node **pnp,
210 bool dryrun)
211{
212 struct device_node *np;
213 const char *pathp;
214 int len;
215
216 pathp = fdt_get_name(blob, offset, &len);
217 if (!pathp) {
218 *pnp = NULL;
219 return len;
220 }
221
222 len++;
223
224 np = unflatten_dt_alloc(mem, sizeof(struct device_node) + len,
225 __alignof__(struct device_node));
226 if (!dryrun) {
227 char *fn;
228 of_node_init(np);
229 np->full_name = fn = ((char *)np) + sizeof(*np);
230
231 memcpy(fn, pathp, len);
232
233 if (dad != NULL) {
234 np->parent = dad;
235 np->sibling = dad->child;
236 dad->child = np;
237 }
238 }
239
240 populate_properties(blob, offset, mem, np, pathp, dryrun);
241 if (!dryrun) {
242 np->name = of_get_property(np, "name", NULL);
243 if (!np->name)
244 np->name = "<NULL>";
245 }
246
247 *pnp = np;
248 return 0;
249}
250
251static void reverse_nodes(struct device_node *parent)
252{
253 struct device_node *child, *next;
254
255 /* In-depth first */
256 child = parent->child;
257 while (child) {
258 reverse_nodes(child);
259
260 child = child->sibling;
261 }
262
263 /* Reverse the nodes in the child list */
264 child = parent->child;
265 parent->child = NULL;
266 while (child) {
267 next = child->sibling;
268
269 child->sibling = parent->child;
270 parent->child = child;
271 child = next;
272 }
273}
274
275/**
276 * unflatten_dt_nodes - Alloc and populate a device_node from the flat tree
277 * @blob: The parent device tree blob
278 * @mem: Memory chunk to use for allocating device nodes and properties
279 * @dad: Parent struct device_node
280 * @nodepp: The device_node tree created by the call
281 *
282 * Return: The size of unflattened device tree or error code
283 */
284static int unflatten_dt_nodes(const void *blob,
285 void *mem,
286 struct device_node *dad,
287 struct device_node **nodepp)
288{
289 struct device_node *root;
290 int offset = 0, depth = 0, initial_depth = 0;
291#define FDT_MAX_DEPTH 64
292 struct device_node *nps[FDT_MAX_DEPTH];
293 void *base = mem;
294 bool dryrun = !base;
295 int ret;
296
297 if (nodepp)
298 *nodepp = NULL;
299
300 /*
301 * We're unflattening device sub-tree if @dad is valid. There are
302 * possibly multiple nodes in the first level of depth. We need
303 * set @depth to 1 to make fdt_next_node() happy as it bails
304 * immediately when negative @depth is found. Otherwise, the device
305 * nodes except the first one won't be unflattened successfully.
306 */
307 if (dad)
308 depth = initial_depth = 1;
309
310 root = dad;
311 nps[depth] = dad;
312
313 for (offset = 0;
314 offset >= 0 && depth >= initial_depth;
315 offset = fdt_next_node(blob, offset, &depth)) {
316 if (WARN_ON_ONCE(depth >= FDT_MAX_DEPTH - 1))
317 continue;
318
319 if (!IS_ENABLED(CONFIG_OF_KOBJ) &&
320 !of_fdt_device_is_available(blob, offset))
321 continue;
322
323 ret = populate_node(blob, offset, &mem, nps[depth],
324 &nps[depth+1], dryrun);
325 if (ret < 0)
326 return ret;
327
328 if (!dryrun && nodepp && !*nodepp)
329 *nodepp = nps[depth+1];
330 if (!dryrun && !root)
331 root = nps[depth+1];
332 }
333
334 if (offset < 0 && offset != -FDT_ERR_NOTFOUND) {
335 pr_err("Error %d processing FDT\n", offset);
336 return -EINVAL;
337 }
338
339 /*
340 * Reverse the child list. Some drivers assumes node order matches .dts
341 * node order
342 */
343 if (!dryrun)
344 reverse_nodes(root);
345
346 return mem - base;
347}
348
349/**
350 * __unflatten_device_tree - create tree of device_nodes from flat blob
351 * @blob: The blob to expand
352 * @dad: Parent device node
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 * @detached: if true set OF_DETACHED on @mynodes
357 *
358 * unflattens a device-tree, creating the tree of struct device_node. It also
359 * fills the "name" and "type" pointers of the nodes so the normal device-tree
360 * walking functions can be used.
361 *
362 * Return: NULL on failure or the memory chunk containing the unflattened
363 * device tree on success.
364 */
365void *__unflatten_device_tree(const void *blob,
366 struct device_node *dad,
367 struct device_node **mynodes,
368 void *(*dt_alloc)(u64 size, u64 align),
369 bool detached)
370{
371 int size;
372 void *mem;
373 int ret;
374
375 if (mynodes)
376 *mynodes = NULL;
377
378 pr_debug(" -> unflatten_device_tree()\n");
379
380 if (!blob) {
381 pr_debug("No device tree pointer\n");
382 return NULL;
383 }
384
385 pr_debug("Unflattening device tree:\n");
386 pr_debug("magic: %08x\n", fdt_magic(blob));
387 pr_debug("size: %08x\n", fdt_totalsize(blob));
388 pr_debug("version: %08x\n", fdt_version(blob));
389
390 if (fdt_check_header(blob)) {
391 pr_err("Invalid device tree blob header\n");
392 return NULL;
393 }
394
395 /* First pass, scan for size */
396 size = unflatten_dt_nodes(blob, NULL, dad, NULL);
397 if (size <= 0)
398 return NULL;
399
400 size = ALIGN(size, 4);
401 pr_debug(" size is %d, allocating...\n", size);
402
403 /* Allocate memory for the expanded device tree */
404 mem = dt_alloc(size + 4, __alignof__(struct device_node));
405 if (!mem)
406 return NULL;
407
408 memset(mem, 0, size);
409
410 *(__be32 *)(mem + size) = cpu_to_be32(0xdeadbeef);
411
412 pr_debug(" unflattening %p...\n", mem);
413
414 /* Second pass, do actual unflattening */
415 ret = unflatten_dt_nodes(blob, mem, dad, mynodes);
416
417 if (be32_to_cpup(mem + size) != 0xdeadbeef)
418 pr_warn("End of tree marker overwritten: %08x\n",
419 be32_to_cpup(mem + size));
420
421 if (ret <= 0)
422 return NULL;
423
424 if (detached && mynodes && *mynodes) {
425 of_node_set_flag(*mynodes, OF_DETACHED);
426 pr_debug("unflattened tree is detached\n");
427 }
428
429 pr_debug(" <- unflatten_device_tree()\n");
430 return mem;
431}
432
433static void *kernel_tree_alloc(u64 size, u64 align)
434{
435 return kzalloc(size, GFP_KERNEL);
436}
437
438static DEFINE_MUTEX(of_fdt_unflatten_mutex);
439
440/**
441 * of_fdt_unflatten_tree - create tree of device_nodes from flat blob
442 * @blob: Flat device tree blob
443 * @dad: Parent device node
444 * @mynodes: The device tree created by the call
445 *
446 * unflattens the device-tree passed by the firmware, creating the
447 * tree of struct device_node. It also fills the "name" and "type"
448 * pointers of the nodes so the normal device-tree walking functions
449 * can be used.
450 *
451 * Return: NULL on failure or the memory chunk containing the unflattened
452 * device tree on success.
453 */
454void *of_fdt_unflatten_tree(const unsigned long *blob,
455 struct device_node *dad,
456 struct device_node **mynodes)
457{
458 void *mem;
459
460 mutex_lock(&of_fdt_unflatten_mutex);
461 mem = __unflatten_device_tree(blob, dad, mynodes, &kernel_tree_alloc,
462 true);
463 mutex_unlock(&of_fdt_unflatten_mutex);
464
465 return mem;
466}
467EXPORT_SYMBOL_GPL(of_fdt_unflatten_tree);
468
469/* Everything below here references initial_boot_params directly. */
470int __initdata dt_root_addr_cells;
471int __initdata dt_root_size_cells;
472
473void *initial_boot_params __ro_after_init;
474
475#ifdef CONFIG_OF_EARLY_FLATTREE
476
477static u32 of_fdt_crc32;
478
479static int __init early_init_dt_reserve_memory(phys_addr_t base,
480 phys_addr_t size, bool nomap)
481{
482 if (nomap) {
483 /*
484 * If the memory is already reserved (by another region), we
485 * should not allow it to be marked nomap, but don't worry
486 * if the region isn't memory as it won't be mapped.
487 */
488 if (memblock_overlaps_region(&memblock.memory, base, size) &&
489 memblock_is_region_reserved(base, size))
490 return -EBUSY;
491
492 return memblock_mark_nomap(base, size);
493 }
494 return memblock_reserve(base, size);
495}
496
497/*
498 * __reserved_mem_reserve_reg() - reserve all memory described in 'reg' property
499 */
500static int __init __reserved_mem_reserve_reg(unsigned long node,
501 const char *uname)
502{
503 int t_len = (dt_root_addr_cells + dt_root_size_cells) * sizeof(__be32);
504 phys_addr_t base, size;
505 int len;
506 const __be32 *prop;
507 int first = 1;
508 bool nomap;
509
510 prop = of_get_flat_dt_prop(node, "reg", &len);
511 if (!prop)
512 return -ENOENT;
513
514 if (len && len % t_len != 0) {
515 pr_err("Reserved memory: invalid reg property in '%s', skipping node.\n",
516 uname);
517 return -EINVAL;
518 }
519
520 nomap = of_get_flat_dt_prop(node, "no-map", NULL) != NULL;
521
522 while (len >= t_len) {
523 base = dt_mem_next_cell(dt_root_addr_cells, &prop);
524 size = dt_mem_next_cell(dt_root_size_cells, &prop);
525
526 if (size &&
527 early_init_dt_reserve_memory(base, size, nomap) == 0)
528 pr_debug("Reserved memory: reserved region for node '%s': base %pa, size %lu MiB\n",
529 uname, &base, (unsigned long)(size / SZ_1M));
530 else
531 pr_err("Reserved memory: failed to reserve memory for node '%s': base %pa, size %lu MiB\n",
532 uname, &base, (unsigned long)(size / SZ_1M));
533
534 len -= t_len;
535 if (first) {
536 fdt_reserved_mem_save_node(node, uname, base, size);
537 first = 0;
538 }
539 }
540 return 0;
541}
542
543/*
544 * __reserved_mem_check_root() - check if #size-cells, #address-cells provided
545 * in /reserved-memory matches the values supported by the current implementation,
546 * also check if ranges property has been provided
547 */
548static int __init __reserved_mem_check_root(unsigned long node)
549{
550 const __be32 *prop;
551
552 prop = of_get_flat_dt_prop(node, "#size-cells", NULL);
553 if (!prop || be32_to_cpup(prop) != dt_root_size_cells)
554 return -EINVAL;
555
556 prop = of_get_flat_dt_prop(node, "#address-cells", NULL);
557 if (!prop || be32_to_cpup(prop) != dt_root_addr_cells)
558 return -EINVAL;
559
560 prop = of_get_flat_dt_prop(node, "ranges", NULL);
561 if (!prop)
562 return -EINVAL;
563 return 0;
564}
565
566/*
567 * fdt_scan_reserved_mem() - scan a single FDT node for reserved memory
568 */
569static int __init fdt_scan_reserved_mem(void)
570{
571 int node, child;
572 const void *fdt = initial_boot_params;
573
574 node = fdt_path_offset(fdt, "/reserved-memory");
575 if (node < 0)
576 return -ENODEV;
577
578 if (__reserved_mem_check_root(node) != 0) {
579 pr_err("Reserved memory: unsupported node format, ignoring\n");
580 return -EINVAL;
581 }
582
583 fdt_for_each_subnode(child, fdt, node) {
584 const char *uname;
585 int err;
586
587 if (!of_fdt_device_is_available(fdt, child))
588 continue;
589
590 uname = fdt_get_name(fdt, child, NULL);
591
592 err = __reserved_mem_reserve_reg(child, uname);
593 if (err == -ENOENT && of_get_flat_dt_prop(child, "size", NULL))
594 fdt_reserved_mem_save_node(child, uname, 0, 0);
595 }
596 return 0;
597}
598
599/*
600 * fdt_reserve_elfcorehdr() - reserves memory for elf core header
601 *
602 * This function reserves the memory occupied by an elf core header
603 * described in the device tree. This region contains all the
604 * information about primary kernel's core image and is used by a dump
605 * capture kernel to access the system memory on primary kernel.
606 */
607static void __init fdt_reserve_elfcorehdr(void)
608{
609 if (!IS_ENABLED(CONFIG_CRASH_DUMP) || !elfcorehdr_size)
610 return;
611
612 if (memblock_is_region_reserved(elfcorehdr_addr, elfcorehdr_size)) {
613 pr_warn("elfcorehdr is overlapped\n");
614 return;
615 }
616
617 memblock_reserve(elfcorehdr_addr, elfcorehdr_size);
618
619 pr_info("Reserving %llu KiB of memory at 0x%llx for elfcorehdr\n",
620 elfcorehdr_size >> 10, elfcorehdr_addr);
621}
622
623/**
624 * early_init_fdt_scan_reserved_mem() - create reserved memory regions
625 *
626 * This function grabs memory from early allocator for device exclusive use
627 * defined in device tree structures. It should be called by arch specific code
628 * once the early allocator (i.e. memblock) has been fully activated.
629 */
630void __init early_init_fdt_scan_reserved_mem(void)
631{
632 int n;
633 u64 base, size;
634
635 if (!initial_boot_params)
636 return;
637
638 fdt_scan_reserved_mem();
639 fdt_reserve_elfcorehdr();
640
641 /* Process header /memreserve/ fields */
642 for (n = 0; ; n++) {
643 fdt_get_mem_rsv(initial_boot_params, n, &base, &size);
644 if (!size)
645 break;
646 memblock_reserve(base, size);
647 }
648
649 fdt_init_reserved_mem();
650}
651
652/**
653 * early_init_fdt_reserve_self() - reserve the memory used by the FDT blob
654 */
655void __init early_init_fdt_reserve_self(void)
656{
657 if (!initial_boot_params)
658 return;
659
660 /* Reserve the dtb region */
661 memblock_reserve(__pa(initial_boot_params),
662 fdt_totalsize(initial_boot_params));
663}
664
665/**
666 * of_scan_flat_dt - scan flattened tree blob and call callback on each.
667 * @it: callback function
668 * @data: context data pointer
669 *
670 * This function is used to scan the flattened device-tree, it is
671 * used to extract the memory information at boot before we can
672 * unflatten the tree
673 */
674int __init of_scan_flat_dt(int (*it)(unsigned long node,
675 const char *uname, int depth,
676 void *data),
677 void *data)
678{
679 const void *blob = initial_boot_params;
680 const char *pathp;
681 int offset, rc = 0, depth = -1;
682
683 if (!blob)
684 return 0;
685
686 for (offset = fdt_next_node(blob, -1, &depth);
687 offset >= 0 && depth >= 0 && !rc;
688 offset = fdt_next_node(blob, offset, &depth)) {
689
690 pathp = fdt_get_name(blob, offset, NULL);
691 rc = it(offset, pathp, depth, data);
692 }
693 return rc;
694}
695
696/**
697 * of_scan_flat_dt_subnodes - scan sub-nodes of a node call callback on each.
698 * @parent: parent node
699 * @it: callback function
700 * @data: context data pointer
701 *
702 * This function is used to scan sub-nodes of a node.
703 */
704int __init of_scan_flat_dt_subnodes(unsigned long parent,
705 int (*it)(unsigned long node,
706 const char *uname,
707 void *data),
708 void *data)
709{
710 const void *blob = initial_boot_params;
711 int node;
712
713 fdt_for_each_subnode(node, blob, parent) {
714 const char *pathp;
715 int rc;
716
717 pathp = fdt_get_name(blob, node, NULL);
718 rc = it(node, pathp, data);
719 if (rc)
720 return rc;
721 }
722 return 0;
723}
724
725/**
726 * of_get_flat_dt_subnode_by_name - get the subnode by given name
727 *
728 * @node: the parent node
729 * @uname: the name of subnode
730 * @return offset of the subnode, or -FDT_ERR_NOTFOUND if there is none
731 */
732
733int __init of_get_flat_dt_subnode_by_name(unsigned long node, const char *uname)
734{
735 return fdt_subnode_offset(initial_boot_params, node, uname);
736}
737
738/*
739 * of_get_flat_dt_root - find the root node in the flat blob
740 */
741unsigned long __init of_get_flat_dt_root(void)
742{
743 return 0;
744}
745
746/*
747 * of_get_flat_dt_prop - Given a node in the flat blob, return the property ptr
748 *
749 * This function can be used within scan_flattened_dt callback to get
750 * access to properties
751 */
752const void *__init of_get_flat_dt_prop(unsigned long node, const char *name,
753 int *size)
754{
755 return fdt_getprop(initial_boot_params, node, name, size);
756}
757
758/**
759 * of_fdt_is_compatible - Return true if given node from the given blob has
760 * compat in its compatible list
761 * @blob: A device tree blob
762 * @node: node to test
763 * @compat: compatible string to compare with compatible list.
764 *
765 * Return: a non-zero value on match with smaller values returned for more
766 * specific compatible values.
767 */
768static int of_fdt_is_compatible(const void *blob,
769 unsigned long node, const char *compat)
770{
771 const char *cp;
772 int cplen;
773 unsigned long l, score = 0;
774
775 cp = fdt_getprop(blob, node, "compatible", &cplen);
776 if (cp == NULL)
777 return 0;
778 while (cplen > 0) {
779 score++;
780 if (of_compat_cmp(cp, compat, strlen(compat)) == 0)
781 return score;
782 l = strlen(cp) + 1;
783 cp += l;
784 cplen -= l;
785 }
786
787 return 0;
788}
789
790/**
791 * of_flat_dt_is_compatible - Return true if given node has compat in compatible list
792 * @node: node to test
793 * @compat: compatible string to compare with compatible list.
794 */
795int __init of_flat_dt_is_compatible(unsigned long node, const char *compat)
796{
797 return of_fdt_is_compatible(initial_boot_params, node, compat);
798}
799
800/*
801 * of_flat_dt_match - Return true if node matches a list of compatible values
802 */
803static int __init of_flat_dt_match(unsigned long node, const char *const *compat)
804{
805 unsigned int tmp, score = 0;
806
807 if (!compat)
808 return 0;
809
810 while (*compat) {
811 tmp = of_fdt_is_compatible(initial_boot_params, node, *compat);
812 if (tmp && (score == 0 || (tmp < score)))
813 score = tmp;
814 compat++;
815 }
816
817 return score;
818}
819
820/*
821 * of_get_flat_dt_phandle - Given a node in the flat blob, return the phandle
822 */
823uint32_t __init of_get_flat_dt_phandle(unsigned long node)
824{
825 return fdt_get_phandle(initial_boot_params, node);
826}
827
828const char * __init of_flat_dt_get_machine_name(void)
829{
830 const char *name;
831 unsigned long dt_root = of_get_flat_dt_root();
832
833 name = of_get_flat_dt_prop(dt_root, "model", NULL);
834 if (!name)
835 name = of_get_flat_dt_prop(dt_root, "compatible", NULL);
836 return name;
837}
838
839/**
840 * of_flat_dt_match_machine - Iterate match tables to find matching machine.
841 *
842 * @default_match: A machine specific ptr to return in case of no match.
843 * @get_next_compat: callback function to return next compatible match table.
844 *
845 * Iterate through machine match tables to find the best match for the machine
846 * compatible string in the FDT.
847 */
848const void * __init of_flat_dt_match_machine(const void *default_match,
849 const void * (*get_next_compat)(const char * const**))
850{
851 const void *data = NULL;
852 const void *best_data = default_match;
853 const char *const *compat;
854 unsigned long dt_root;
855 unsigned int best_score = ~1, score = 0;
856
857 dt_root = of_get_flat_dt_root();
858 while ((data = get_next_compat(&compat))) {
859 score = of_flat_dt_match(dt_root, compat);
860 if (score > 0 && score < best_score) {
861 best_data = data;
862 best_score = score;
863 }
864 }
865 if (!best_data) {
866 const char *prop;
867 int size;
868
869 pr_err("\n unrecognized device tree list:\n[ ");
870
871 prop = of_get_flat_dt_prop(dt_root, "compatible", &size);
872 if (prop) {
873 while (size > 0) {
874 printk("'%s' ", prop);
875 size -= strlen(prop) + 1;
876 prop += strlen(prop) + 1;
877 }
878 }
879 printk("]\n\n");
880 return NULL;
881 }
882
883 pr_info("Machine model: %s\n", of_flat_dt_get_machine_name());
884
885 return best_data;
886}
887
888static void __early_init_dt_declare_initrd(unsigned long start,
889 unsigned long end)
890{
891 /*
892 * __va() is not yet available this early on some platforms. In that
893 * case, the platform uses phys_initrd_start/phys_initrd_size instead
894 * and does the VA conversion itself.
895 */
896 if (!IS_ENABLED(CONFIG_ARM64) &&
897 !(IS_ENABLED(CONFIG_RISCV) && IS_ENABLED(CONFIG_64BIT))) {
898 initrd_start = (unsigned long)__va(start);
899 initrd_end = (unsigned long)__va(end);
900 initrd_below_start_ok = 1;
901 }
902}
903
904/**
905 * early_init_dt_check_for_initrd - Decode initrd location from flat tree
906 * @node: reference to node containing initrd location ('chosen')
907 */
908static void __init early_init_dt_check_for_initrd(unsigned long node)
909{
910 u64 start, end;
911 int len;
912 const __be32 *prop;
913
914 if (!IS_ENABLED(CONFIG_BLK_DEV_INITRD))
915 return;
916
917 pr_debug("Looking for initrd properties... ");
918
919 prop = of_get_flat_dt_prop(node, "linux,initrd-start", &len);
920 if (!prop)
921 return;
922 start = of_read_number(prop, len/4);
923
924 prop = of_get_flat_dt_prop(node, "linux,initrd-end", &len);
925 if (!prop)
926 return;
927 end = of_read_number(prop, len/4);
928 if (start > end)
929 return;
930
931 __early_init_dt_declare_initrd(start, end);
932 phys_initrd_start = start;
933 phys_initrd_size = end - start;
934
935 pr_debug("initrd_start=0x%llx initrd_end=0x%llx\n", start, end);
936}
937
938/**
939 * early_init_dt_check_for_elfcorehdr - Decode elfcorehdr location from flat
940 * tree
941 * @node: reference to node containing elfcorehdr location ('chosen')
942 */
943static void __init early_init_dt_check_for_elfcorehdr(unsigned long node)
944{
945 const __be32 *prop;
946 int len;
947
948 if (!IS_ENABLED(CONFIG_CRASH_DUMP))
949 return;
950
951 pr_debug("Looking for elfcorehdr property... ");
952
953 prop = of_get_flat_dt_prop(node, "linux,elfcorehdr", &len);
954 if (!prop || (len < (dt_root_addr_cells + dt_root_size_cells)))
955 return;
956
957 elfcorehdr_addr = dt_mem_next_cell(dt_root_addr_cells, &prop);
958 elfcorehdr_size = dt_mem_next_cell(dt_root_size_cells, &prop);
959
960 pr_debug("elfcorehdr_start=0x%llx elfcorehdr_size=0x%llx\n",
961 elfcorehdr_addr, elfcorehdr_size);
962}
963
964static unsigned long chosen_node_offset = -FDT_ERR_NOTFOUND;
965
966/*
967 * The main usage of linux,usable-memory-range is for crash dump kernel.
968 * Originally, the number of usable-memory regions is one. Now there may
969 * be two regions, low region and high region.
970 * To make compatibility with existing user-space and older kdump, the low
971 * region is always the last range of linux,usable-memory-range if exist.
972 */
973#define MAX_USABLE_RANGES 2
974
975/**
976 * early_init_dt_check_for_usable_mem_range - Decode usable memory range
977 * location from flat tree
978 */
979void __init early_init_dt_check_for_usable_mem_range(void)
980{
981 struct memblock_region rgn[MAX_USABLE_RANGES] = {0};
982 const __be32 *prop, *endp;
983 int len, i;
984 unsigned long node = chosen_node_offset;
985
986 if ((long)node < 0)
987 return;
988
989 pr_debug("Looking for usable-memory-range property... ");
990
991 prop = of_get_flat_dt_prop(node, "linux,usable-memory-range", &len);
992 if (!prop || (len % (dt_root_addr_cells + dt_root_size_cells)))
993 return;
994
995 endp = prop + (len / sizeof(__be32));
996 for (i = 0; i < MAX_USABLE_RANGES && prop < endp; i++) {
997 rgn[i].base = dt_mem_next_cell(dt_root_addr_cells, &prop);
998 rgn[i].size = dt_mem_next_cell(dt_root_size_cells, &prop);
999
1000 pr_debug("cap_mem_regions[%d]: base=%pa, size=%pa\n",
1001 i, &rgn[i].base, &rgn[i].size);
1002 }
1003
1004 memblock_cap_memory_range(rgn[0].base, rgn[0].size);
1005 for (i = 1; i < MAX_USABLE_RANGES && rgn[i].size; i++)
1006 memblock_add(rgn[i].base, rgn[i].size);
1007}
1008
1009#ifdef CONFIG_SERIAL_EARLYCON
1010
1011int __init early_init_dt_scan_chosen_stdout(void)
1012{
1013 int offset;
1014 const char *p, *q, *options = NULL;
1015 int l;
1016 const struct earlycon_id *match;
1017 const void *fdt = initial_boot_params;
1018 int ret;
1019
1020 offset = fdt_path_offset(fdt, "/chosen");
1021 if (offset < 0)
1022 offset = fdt_path_offset(fdt, "/chosen@0");
1023 if (offset < 0)
1024 return -ENOENT;
1025
1026 p = fdt_getprop(fdt, offset, "stdout-path", &l);
1027 if (!p)
1028 p = fdt_getprop(fdt, offset, "linux,stdout-path", &l);
1029 if (!p || !l)
1030 return -ENOENT;
1031
1032 q = strchrnul(p, ':');
1033 if (*q != '\0')
1034 options = q + 1;
1035 l = q - p;
1036
1037 /* Get the node specified by stdout-path */
1038 offset = fdt_path_offset_namelen(fdt, p, l);
1039 if (offset < 0) {
1040 pr_warn("earlycon: stdout-path %.*s not found\n", l, p);
1041 return 0;
1042 }
1043
1044 for (match = __earlycon_table; match < __earlycon_table_end; match++) {
1045 if (!match->compatible[0])
1046 continue;
1047
1048 if (fdt_node_check_compatible(fdt, offset, match->compatible))
1049 continue;
1050
1051 ret = of_setup_earlycon(match, offset, options);
1052 if (!ret || ret == -EALREADY)
1053 return 0;
1054 }
1055 return -ENODEV;
1056}
1057#endif
1058
1059/*
1060 * early_init_dt_scan_root - fetch the top level address and size cells
1061 */
1062int __init early_init_dt_scan_root(void)
1063{
1064 const __be32 *prop;
1065 const void *fdt = initial_boot_params;
1066 int node = fdt_path_offset(fdt, "/");
1067
1068 if (node < 0)
1069 return -ENODEV;
1070
1071 dt_root_size_cells = OF_ROOT_NODE_SIZE_CELLS_DEFAULT;
1072 dt_root_addr_cells = OF_ROOT_NODE_ADDR_CELLS_DEFAULT;
1073
1074 prop = of_get_flat_dt_prop(node, "#size-cells", NULL);
1075 if (prop)
1076 dt_root_size_cells = be32_to_cpup(prop);
1077 pr_debug("dt_root_size_cells = %x\n", dt_root_size_cells);
1078
1079 prop = of_get_flat_dt_prop(node, "#address-cells", NULL);
1080 if (prop)
1081 dt_root_addr_cells = be32_to_cpup(prop);
1082 pr_debug("dt_root_addr_cells = %x\n", dt_root_addr_cells);
1083
1084 return 0;
1085}
1086
1087u64 __init dt_mem_next_cell(int s, const __be32 **cellp)
1088{
1089 const __be32 *p = *cellp;
1090
1091 *cellp = p + s;
1092 return of_read_number(p, s);
1093}
1094
1095/*
1096 * early_init_dt_scan_memory - Look for and parse memory nodes
1097 */
1098int __init early_init_dt_scan_memory(void)
1099{
1100 int node, found_memory = 0;
1101 const void *fdt = initial_boot_params;
1102
1103 fdt_for_each_subnode(node, fdt, 0) {
1104 const char *type = of_get_flat_dt_prop(node, "device_type", NULL);
1105 const __be32 *reg, *endp;
1106 int l;
1107 bool hotpluggable;
1108
1109 /* We are scanning "memory" nodes only */
1110 if (type == NULL || strcmp(type, "memory") != 0)
1111 continue;
1112
1113 if (!of_fdt_device_is_available(fdt, node))
1114 continue;
1115
1116 reg = of_get_flat_dt_prop(node, "linux,usable-memory", &l);
1117 if (reg == NULL)
1118 reg = of_get_flat_dt_prop(node, "reg", &l);
1119 if (reg == NULL)
1120 continue;
1121
1122 endp = reg + (l / sizeof(__be32));
1123 hotpluggable = of_get_flat_dt_prop(node, "hotpluggable", NULL);
1124
1125 pr_debug("memory scan node %s, reg size %d,\n",
1126 fdt_get_name(fdt, node, NULL), l);
1127
1128 while ((endp - reg) >= (dt_root_addr_cells + dt_root_size_cells)) {
1129 u64 base, size;
1130
1131 base = dt_mem_next_cell(dt_root_addr_cells, ®);
1132 size = dt_mem_next_cell(dt_root_size_cells, ®);
1133
1134 if (size == 0)
1135 continue;
1136 pr_debug(" - %llx, %llx\n", base, size);
1137
1138 early_init_dt_add_memory_arch(base, size);
1139
1140 found_memory = 1;
1141
1142 if (!hotpluggable)
1143 continue;
1144
1145 if (memblock_mark_hotplug(base, size))
1146 pr_warn("failed to mark hotplug range 0x%llx - 0x%llx\n",
1147 base, base + size);
1148 }
1149 }
1150 return found_memory;
1151}
1152
1153int __init early_init_dt_scan_chosen(char *cmdline)
1154{
1155 int l, node;
1156 const char *p;
1157 const void *rng_seed;
1158 const void *fdt = initial_boot_params;
1159
1160 node = fdt_path_offset(fdt, "/chosen");
1161 if (node < 0)
1162 node = fdt_path_offset(fdt, "/chosen@0");
1163 if (node < 0)
1164 /* Handle the cmdline config options even if no /chosen node */
1165 goto handle_cmdline;
1166
1167 chosen_node_offset = node;
1168
1169 early_init_dt_check_for_initrd(node);
1170 early_init_dt_check_for_elfcorehdr(node);
1171
1172 rng_seed = of_get_flat_dt_prop(node, "rng-seed", &l);
1173 if (rng_seed && l > 0) {
1174 add_bootloader_randomness(rng_seed, l);
1175
1176 /* try to clear seed so it won't be found. */
1177 fdt_nop_property(initial_boot_params, node, "rng-seed");
1178
1179 /* update CRC check value */
1180 of_fdt_crc32 = crc32_be(~0, initial_boot_params,
1181 fdt_totalsize(initial_boot_params));
1182 }
1183
1184 /* Retrieve command line */
1185 p = of_get_flat_dt_prop(node, "bootargs", &l);
1186 if (p != NULL && l > 0)
1187 strscpy(cmdline, p, min(l, COMMAND_LINE_SIZE));
1188
1189handle_cmdline:
1190 /*
1191 * CONFIG_CMDLINE is meant to be a default in case nothing else
1192 * managed to set the command line, unless CONFIG_CMDLINE_FORCE
1193 * is set in which case we override whatever was found earlier.
1194 */
1195#ifdef CONFIG_CMDLINE
1196#if defined(CONFIG_CMDLINE_EXTEND)
1197 strlcat(cmdline, " ", COMMAND_LINE_SIZE);
1198 strlcat(cmdline, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
1199#elif defined(CONFIG_CMDLINE_FORCE)
1200 strscpy(cmdline, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
1201#else
1202 /* No arguments from boot loader, use kernel's cmdl*/
1203 if (!((char *)cmdline)[0])
1204 strscpy(cmdline, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
1205#endif
1206#endif /* CONFIG_CMDLINE */
1207
1208 pr_debug("Command line is: %s\n", (char *)cmdline);
1209
1210 return 0;
1211}
1212
1213#ifndef MIN_MEMBLOCK_ADDR
1214#define MIN_MEMBLOCK_ADDR __pa(PAGE_OFFSET)
1215#endif
1216#ifndef MAX_MEMBLOCK_ADDR
1217#define MAX_MEMBLOCK_ADDR ((phys_addr_t)~0)
1218#endif
1219
1220void __init __weak early_init_dt_add_memory_arch(u64 base, u64 size)
1221{
1222 const u64 phys_offset = MIN_MEMBLOCK_ADDR;
1223
1224 if (size < PAGE_SIZE - (base & ~PAGE_MASK)) {
1225 pr_warn("Ignoring memory block 0x%llx - 0x%llx\n",
1226 base, base + size);
1227 return;
1228 }
1229
1230 if (!PAGE_ALIGNED(base)) {
1231 size -= PAGE_SIZE - (base & ~PAGE_MASK);
1232 base = PAGE_ALIGN(base);
1233 }
1234 size &= PAGE_MASK;
1235
1236 if (base > MAX_MEMBLOCK_ADDR) {
1237 pr_warn("Ignoring memory block 0x%llx - 0x%llx\n",
1238 base, base + size);
1239 return;
1240 }
1241
1242 if (base + size - 1 > MAX_MEMBLOCK_ADDR) {
1243 pr_warn("Ignoring memory range 0x%llx - 0x%llx\n",
1244 ((u64)MAX_MEMBLOCK_ADDR) + 1, base + size);
1245 size = MAX_MEMBLOCK_ADDR - base + 1;
1246 }
1247
1248 if (base + size < phys_offset) {
1249 pr_warn("Ignoring memory block 0x%llx - 0x%llx\n",
1250 base, base + size);
1251 return;
1252 }
1253 if (base < phys_offset) {
1254 pr_warn("Ignoring memory range 0x%llx - 0x%llx\n",
1255 base, phys_offset);
1256 size -= phys_offset - base;
1257 base = phys_offset;
1258 }
1259 memblock_add(base, size);
1260}
1261
1262static void * __init early_init_dt_alloc_memory_arch(u64 size, u64 align)
1263{
1264 void *ptr = memblock_alloc(size, align);
1265
1266 if (!ptr)
1267 panic("%s: Failed to allocate %llu bytes align=0x%llx\n",
1268 __func__, size, align);
1269
1270 return ptr;
1271}
1272
1273bool __init early_init_dt_verify(void *params)
1274{
1275 if (!params)
1276 return false;
1277
1278 /* check device tree validity */
1279 if (fdt_check_header(params))
1280 return false;
1281
1282 /* Setup flat device-tree pointer */
1283 initial_boot_params = params;
1284 of_fdt_crc32 = crc32_be(~0, initial_boot_params,
1285 fdt_totalsize(initial_boot_params));
1286 return true;
1287}
1288
1289
1290void __init early_init_dt_scan_nodes(void)
1291{
1292 int rc;
1293
1294 /* Initialize {size,address}-cells info */
1295 early_init_dt_scan_root();
1296
1297 /* Retrieve various information from the /chosen node */
1298 rc = early_init_dt_scan_chosen(boot_command_line);
1299 if (rc)
1300 pr_warn("No chosen node found, continuing without\n");
1301
1302 /* Setup memory, calling early_init_dt_add_memory_arch */
1303 early_init_dt_scan_memory();
1304
1305 /* Handle linux,usable-memory-range property */
1306 early_init_dt_check_for_usable_mem_range();
1307}
1308
1309bool __init early_init_dt_scan(void *params)
1310{
1311 bool status;
1312
1313 status = early_init_dt_verify(params);
1314 if (!status)
1315 return false;
1316
1317 early_init_dt_scan_nodes();
1318 return true;
1319}
1320
1321/**
1322 * unflatten_device_tree - create tree of device_nodes from flat blob
1323 *
1324 * unflattens the device-tree passed by the firmware, creating the
1325 * tree of struct device_node. It also fills the "name" and "type"
1326 * pointers of the nodes so the normal device-tree walking functions
1327 * can be used.
1328 */
1329void __init unflatten_device_tree(void)
1330{
1331 __unflatten_device_tree(initial_boot_params, NULL, &of_root,
1332 early_init_dt_alloc_memory_arch, false);
1333
1334 /* Get pointer to "/chosen" and "/aliases" nodes for use everywhere */
1335 of_alias_scan(early_init_dt_alloc_memory_arch);
1336
1337 unittest_unflatten_overlay_base();
1338}
1339
1340/**
1341 * unflatten_and_copy_device_tree - copy and create tree of device_nodes from flat blob
1342 *
1343 * Copies and unflattens the device-tree passed by the firmware, creating the
1344 * tree of struct device_node. It also fills the "name" and "type"
1345 * pointers of the nodes so the normal device-tree walking functions
1346 * can be used. This should only be used when the FDT memory has not been
1347 * reserved such is the case when the FDT is built-in to the kernel init
1348 * section. If the FDT memory is reserved already then unflatten_device_tree
1349 * should be used instead.
1350 */
1351void __init unflatten_and_copy_device_tree(void)
1352{
1353 int size;
1354 void *dt;
1355
1356 if (!initial_boot_params) {
1357 pr_warn("No valid device tree found, continuing without\n");
1358 return;
1359 }
1360
1361 size = fdt_totalsize(initial_boot_params);
1362 dt = early_init_dt_alloc_memory_arch(size,
1363 roundup_pow_of_two(FDT_V17_SIZE));
1364
1365 if (dt) {
1366 memcpy(dt, initial_boot_params, size);
1367 initial_boot_params = dt;
1368 }
1369 unflatten_device_tree();
1370}
1371
1372#ifdef CONFIG_SYSFS
1373static ssize_t of_fdt_raw_read(struct file *filp, struct kobject *kobj,
1374 struct bin_attribute *bin_attr,
1375 char *buf, loff_t off, size_t count)
1376{
1377 memcpy(buf, initial_boot_params + off, count);
1378 return count;
1379}
1380
1381static int __init of_fdt_raw_init(void)
1382{
1383 static struct bin_attribute of_fdt_raw_attr =
1384 __BIN_ATTR(fdt, S_IRUSR, of_fdt_raw_read, NULL, 0);
1385
1386 if (!initial_boot_params)
1387 return 0;
1388
1389 if (of_fdt_crc32 != crc32_be(~0, initial_boot_params,
1390 fdt_totalsize(initial_boot_params))) {
1391 pr_warn("not creating '/sys/firmware/fdt': CRC check failed\n");
1392 return 0;
1393 }
1394 of_fdt_raw_attr.size = fdt_totalsize(initial_boot_params);
1395 return sysfs_create_bin_file(firmware_kobj, &of_fdt_raw_attr);
1396}
1397late_initcall(of_fdt_raw_init);
1398#endif
1399
1400#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 int 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 int len;
218
219 pathp = fdt_get_name(blob, offset, &len);
220 if (!pathp) {
221 *pnp = NULL;
222 return len;
223 }
224
225 len++;
226
227 np = unflatten_dt_alloc(mem, sizeof(struct device_node) + len,
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, len);
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 * Return: 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 int ret;
299
300 if (nodepp)
301 *nodepp = NULL;
302
303 /*
304 * We're unflattening device sub-tree if @dad is valid. There are
305 * possibly multiple nodes in the first level of depth. We need
306 * set @depth to 1 to make fdt_next_node() happy as it bails
307 * immediately when negative @depth is found. Otherwise, the device
308 * nodes except the first one won't be unflattened successfully.
309 */
310 if (dad)
311 depth = initial_depth = 1;
312
313 root = dad;
314 nps[depth] = dad;
315
316 for (offset = 0;
317 offset >= 0 && depth >= initial_depth;
318 offset = fdt_next_node(blob, offset, &depth)) {
319 if (WARN_ON_ONCE(depth >= FDT_MAX_DEPTH))
320 continue;
321
322 if (!IS_ENABLED(CONFIG_OF_KOBJ) &&
323 !of_fdt_device_is_available(blob, offset))
324 continue;
325
326 ret = populate_node(blob, offset, &mem, nps[depth],
327 &nps[depth+1], dryrun);
328 if (ret < 0)
329 return ret;
330
331 if (!dryrun && nodepp && !*nodepp)
332 *nodepp = nps[depth+1];
333 if (!dryrun && !root)
334 root = nps[depth+1];
335 }
336
337 if (offset < 0 && offset != -FDT_ERR_NOTFOUND) {
338 pr_err("Error %d processing FDT\n", offset);
339 return -EINVAL;
340 }
341
342 /*
343 * Reverse the child list. Some drivers assumes node order matches .dts
344 * node order
345 */
346 if (!dryrun)
347 reverse_nodes(root);
348
349 return mem - base;
350}
351
352/**
353 * __unflatten_device_tree - create tree of device_nodes from flat blob
354 * @blob: The blob to expand
355 * @dad: Parent device node
356 * @mynodes: The device_node tree created by the call
357 * @dt_alloc: An allocator that provides a virtual address to memory
358 * for the resulting tree
359 * @detached: if true set OF_DETACHED on @mynodes
360 *
361 * unflattens a device-tree, creating the tree of struct device_node. It also
362 * fills the "name" and "type" pointers of the nodes so the normal device-tree
363 * walking functions can be used.
364 *
365 * Return: NULL on failure or the memory chunk containing the unflattened
366 * device tree on success.
367 */
368void *__unflatten_device_tree(const void *blob,
369 struct device_node *dad,
370 struct device_node **mynodes,
371 void *(*dt_alloc)(u64 size, u64 align),
372 bool detached)
373{
374 int size;
375 void *mem;
376 int ret;
377
378 if (mynodes)
379 *mynodes = NULL;
380
381 pr_debug(" -> unflatten_device_tree()\n");
382
383 if (!blob) {
384 pr_debug("No device tree pointer\n");
385 return NULL;
386 }
387
388 pr_debug("Unflattening device tree:\n");
389 pr_debug("magic: %08x\n", fdt_magic(blob));
390 pr_debug("size: %08x\n", fdt_totalsize(blob));
391 pr_debug("version: %08x\n", fdt_version(blob));
392
393 if (fdt_check_header(blob)) {
394 pr_err("Invalid device tree blob header\n");
395 return NULL;
396 }
397
398 /* First pass, scan for size */
399 size = unflatten_dt_nodes(blob, NULL, dad, NULL);
400 if (size <= 0)
401 return NULL;
402
403 size = ALIGN(size, 4);
404 pr_debug(" size is %d, allocating...\n", size);
405
406 /* Allocate memory for the expanded device tree */
407 mem = dt_alloc(size + 4, __alignof__(struct device_node));
408 if (!mem)
409 return NULL;
410
411 memset(mem, 0, size);
412
413 *(__be32 *)(mem + size) = cpu_to_be32(0xdeadbeef);
414
415 pr_debug(" unflattening %p...\n", mem);
416
417 /* Second pass, do actual unflattening */
418 ret = unflatten_dt_nodes(blob, mem, dad, mynodes);
419
420 if (be32_to_cpup(mem + size) != 0xdeadbeef)
421 pr_warn("End of tree marker overwritten: %08x\n",
422 be32_to_cpup(mem + size));
423
424 if (ret <= 0)
425 return NULL;
426
427 if (detached && mynodes && *mynodes) {
428 of_node_set_flag(*mynodes, OF_DETACHED);
429 pr_debug("unflattened tree is detached\n");
430 }
431
432 pr_debug(" <- unflatten_device_tree()\n");
433 return mem;
434}
435
436static void *kernel_tree_alloc(u64 size, u64 align)
437{
438 return kzalloc(size, GFP_KERNEL);
439}
440
441static DEFINE_MUTEX(of_fdt_unflatten_mutex);
442
443/**
444 * of_fdt_unflatten_tree - create tree of device_nodes from flat blob
445 * @blob: Flat device tree blob
446 * @dad: Parent device node
447 * @mynodes: The device tree created by the call
448 *
449 * unflattens the device-tree passed by the firmware, creating the
450 * tree of struct device_node. It also fills the "name" and "type"
451 * pointers of the nodes so the normal device-tree walking functions
452 * can be used.
453 *
454 * Return: NULL on failure or the memory chunk containing the unflattened
455 * device tree on success.
456 */
457void *of_fdt_unflatten_tree(const unsigned long *blob,
458 struct device_node *dad,
459 struct device_node **mynodes)
460{
461 void *mem;
462
463 mutex_lock(&of_fdt_unflatten_mutex);
464 mem = __unflatten_device_tree(blob, dad, mynodes, &kernel_tree_alloc,
465 true);
466 mutex_unlock(&of_fdt_unflatten_mutex);
467
468 return mem;
469}
470EXPORT_SYMBOL_GPL(of_fdt_unflatten_tree);
471
472/* Everything below here references initial_boot_params directly. */
473int __initdata dt_root_addr_cells;
474int __initdata dt_root_size_cells;
475
476void *initial_boot_params __ro_after_init;
477
478#ifdef CONFIG_OF_EARLY_FLATTREE
479
480static u32 of_fdt_crc32;
481
482/*
483 * __reserved_mem_reserve_reg() - reserve all memory described in 'reg' property
484 */
485static int __init __reserved_mem_reserve_reg(unsigned long node,
486 const char *uname)
487{
488 int t_len = (dt_root_addr_cells + dt_root_size_cells) * sizeof(__be32);
489 phys_addr_t base, size;
490 int len;
491 const __be32 *prop;
492 int first = 1;
493 bool nomap;
494
495 prop = of_get_flat_dt_prop(node, "reg", &len);
496 if (!prop)
497 return -ENOENT;
498
499 if (len && len % t_len != 0) {
500 pr_err("Reserved memory: invalid reg property in '%s', skipping node.\n",
501 uname);
502 return -EINVAL;
503 }
504
505 nomap = of_get_flat_dt_prop(node, "no-map", NULL) != NULL;
506
507 while (len >= t_len) {
508 base = dt_mem_next_cell(dt_root_addr_cells, &prop);
509 size = dt_mem_next_cell(dt_root_size_cells, &prop);
510
511 if (size &&
512 early_init_dt_reserve_memory_arch(base, size, nomap) == 0)
513 pr_debug("Reserved memory: reserved region for node '%s': base %pa, size %lu MiB\n",
514 uname, &base, (unsigned long)(size / SZ_1M));
515 else
516 pr_info("Reserved memory: failed to reserve memory for node '%s': base %pa, size %lu MiB\n",
517 uname, &base, (unsigned long)(size / SZ_1M));
518
519 len -= t_len;
520 if (first) {
521 fdt_reserved_mem_save_node(node, uname, base, size);
522 first = 0;
523 }
524 }
525 return 0;
526}
527
528/*
529 * __reserved_mem_check_root() - check if #size-cells, #address-cells provided
530 * in /reserved-memory matches the values supported by the current implementation,
531 * also check if ranges property has been provided
532 */
533static int __init __reserved_mem_check_root(unsigned long node)
534{
535 const __be32 *prop;
536
537 prop = of_get_flat_dt_prop(node, "#size-cells", NULL);
538 if (!prop || be32_to_cpup(prop) != dt_root_size_cells)
539 return -EINVAL;
540
541 prop = of_get_flat_dt_prop(node, "#address-cells", NULL);
542 if (!prop || be32_to_cpup(prop) != dt_root_addr_cells)
543 return -EINVAL;
544
545 prop = of_get_flat_dt_prop(node, "ranges", NULL);
546 if (!prop)
547 return -EINVAL;
548 return 0;
549}
550
551/*
552 * __fdt_scan_reserved_mem() - scan a single FDT node for reserved memory
553 */
554static int __init __fdt_scan_reserved_mem(unsigned long node, const char *uname,
555 int depth, void *data)
556{
557 static int found;
558 int err;
559
560 if (!found && depth == 1 && strcmp(uname, "reserved-memory") == 0) {
561 if (__reserved_mem_check_root(node) != 0) {
562 pr_err("Reserved memory: unsupported node format, ignoring\n");
563 /* break scan */
564 return 1;
565 }
566 found = 1;
567 /* scan next node */
568 return 0;
569 } else if (!found) {
570 /* scan next node */
571 return 0;
572 } else if (found && depth < 2) {
573 /* scanning of /reserved-memory has been finished */
574 return 1;
575 }
576
577 if (!of_fdt_device_is_available(initial_boot_params, node))
578 return 0;
579
580 err = __reserved_mem_reserve_reg(node, uname);
581 if (err == -ENOENT && of_get_flat_dt_prop(node, "size", NULL))
582 fdt_reserved_mem_save_node(node, uname, 0, 0);
583
584 /* scan next node */
585 return 0;
586}
587
588/**
589 * early_init_fdt_scan_reserved_mem() - create reserved memory regions
590 *
591 * This function grabs memory from early allocator for device exclusive use
592 * defined in device tree structures. It should be called by arch specific code
593 * once the early allocator (i.e. memblock) has been fully activated.
594 */
595void __init early_init_fdt_scan_reserved_mem(void)
596{
597 int n;
598 u64 base, size;
599
600 if (!initial_boot_params)
601 return;
602
603 /* Process header /memreserve/ fields */
604 for (n = 0; ; n++) {
605 fdt_get_mem_rsv(initial_boot_params, n, &base, &size);
606 if (!size)
607 break;
608 early_init_dt_reserve_memory_arch(base, size, false);
609 }
610
611 of_scan_flat_dt(__fdt_scan_reserved_mem, NULL);
612 fdt_init_reserved_mem();
613}
614
615/**
616 * early_init_fdt_reserve_self() - reserve the memory used by the FDT blob
617 */
618void __init early_init_fdt_reserve_self(void)
619{
620 if (!initial_boot_params)
621 return;
622
623 /* Reserve the dtb region */
624 early_init_dt_reserve_memory_arch(__pa(initial_boot_params),
625 fdt_totalsize(initial_boot_params),
626 false);
627}
628
629/**
630 * of_scan_flat_dt - scan flattened tree blob and call callback on each.
631 * @it: callback function
632 * @data: context data pointer
633 *
634 * This function is used to scan the flattened device-tree, it is
635 * used to extract the memory information at boot before we can
636 * unflatten the tree
637 */
638int __init of_scan_flat_dt(int (*it)(unsigned long node,
639 const char *uname, int depth,
640 void *data),
641 void *data)
642{
643 const void *blob = initial_boot_params;
644 const char *pathp;
645 int offset, rc = 0, depth = -1;
646
647 if (!blob)
648 return 0;
649
650 for (offset = fdt_next_node(blob, -1, &depth);
651 offset >= 0 && depth >= 0 && !rc;
652 offset = fdt_next_node(blob, offset, &depth)) {
653
654 pathp = fdt_get_name(blob, offset, NULL);
655 rc = it(offset, pathp, depth, data);
656 }
657 return rc;
658}
659
660/**
661 * of_scan_flat_dt_subnodes - scan sub-nodes of a node call callback on each.
662 * @parent: parent node
663 * @it: callback function
664 * @data: context data pointer
665 *
666 * This function is used to scan sub-nodes of a node.
667 */
668int __init of_scan_flat_dt_subnodes(unsigned long parent,
669 int (*it)(unsigned long node,
670 const char *uname,
671 void *data),
672 void *data)
673{
674 const void *blob = initial_boot_params;
675 int node;
676
677 fdt_for_each_subnode(node, blob, parent) {
678 const char *pathp;
679 int rc;
680
681 pathp = fdt_get_name(blob, node, NULL);
682 rc = it(node, pathp, data);
683 if (rc)
684 return rc;
685 }
686 return 0;
687}
688
689/**
690 * of_get_flat_dt_subnode_by_name - get the subnode by given name
691 *
692 * @node: the parent node
693 * @uname: the name of subnode
694 * @return offset of the subnode, or -FDT_ERR_NOTFOUND if there is none
695 */
696
697int __init of_get_flat_dt_subnode_by_name(unsigned long node, const char *uname)
698{
699 return fdt_subnode_offset(initial_boot_params, node, uname);
700}
701
702/*
703 * of_get_flat_dt_root - find the root node in the flat blob
704 */
705unsigned long __init of_get_flat_dt_root(void)
706{
707 return 0;
708}
709
710/*
711 * of_get_flat_dt_prop - Given a node in the flat blob, return the property ptr
712 *
713 * This function can be used within scan_flattened_dt callback to get
714 * access to properties
715 */
716const void *__init of_get_flat_dt_prop(unsigned long node, const char *name,
717 int *size)
718{
719 return fdt_getprop(initial_boot_params, node, name, size);
720}
721
722/**
723 * of_fdt_is_compatible - Return true if given node from the given blob has
724 * compat in its compatible list
725 * @blob: A device tree blob
726 * @node: node to test
727 * @compat: compatible string to compare with compatible list.
728 *
729 * Return: a non-zero value on match with smaller values returned for more
730 * specific compatible values.
731 */
732static int of_fdt_is_compatible(const void *blob,
733 unsigned long node, const char *compat)
734{
735 const char *cp;
736 int cplen;
737 unsigned long l, score = 0;
738
739 cp = fdt_getprop(blob, node, "compatible", &cplen);
740 if (cp == NULL)
741 return 0;
742 while (cplen > 0) {
743 score++;
744 if (of_compat_cmp(cp, compat, strlen(compat)) == 0)
745 return score;
746 l = strlen(cp) + 1;
747 cp += l;
748 cplen -= l;
749 }
750
751 return 0;
752}
753
754/**
755 * of_flat_dt_is_compatible - Return true if given node has compat in compatible list
756 * @node: node to test
757 * @compat: compatible string to compare with compatible list.
758 */
759int __init of_flat_dt_is_compatible(unsigned long node, const char *compat)
760{
761 return of_fdt_is_compatible(initial_boot_params, node, compat);
762}
763
764/*
765 * of_flat_dt_match - Return true if node matches a list of compatible values
766 */
767static int __init of_flat_dt_match(unsigned long node, const char *const *compat)
768{
769 unsigned int tmp, score = 0;
770
771 if (!compat)
772 return 0;
773
774 while (*compat) {
775 tmp = of_fdt_is_compatible(initial_boot_params, node, *compat);
776 if (tmp && (score == 0 || (tmp < score)))
777 score = tmp;
778 compat++;
779 }
780
781 return score;
782}
783
784/*
785 * of_get_flat_dt_phandle - Given a node in the flat blob, return the phandle
786 */
787uint32_t __init of_get_flat_dt_phandle(unsigned long node)
788{
789 return fdt_get_phandle(initial_boot_params, node);
790}
791
792struct fdt_scan_status {
793 const char *name;
794 int namelen;
795 int depth;
796 int found;
797 int (*iterator)(unsigned long node, const char *uname, int depth, void *data);
798 void *data;
799};
800
801const char * __init of_flat_dt_get_machine_name(void)
802{
803 const char *name;
804 unsigned long dt_root = of_get_flat_dt_root();
805
806 name = of_get_flat_dt_prop(dt_root, "model", NULL);
807 if (!name)
808 name = of_get_flat_dt_prop(dt_root, "compatible", NULL);
809 return name;
810}
811
812/**
813 * of_flat_dt_match_machine - Iterate match tables to find matching machine.
814 *
815 * @default_match: A machine specific ptr to return in case of no match.
816 * @get_next_compat: callback function to return next compatible match table.
817 *
818 * Iterate through machine match tables to find the best match for the machine
819 * compatible string in the FDT.
820 */
821const void * __init of_flat_dt_match_machine(const void *default_match,
822 const void * (*get_next_compat)(const char * const**))
823{
824 const void *data = NULL;
825 const void *best_data = default_match;
826 const char *const *compat;
827 unsigned long dt_root;
828 unsigned int best_score = ~1, score = 0;
829
830 dt_root = of_get_flat_dt_root();
831 while ((data = get_next_compat(&compat))) {
832 score = of_flat_dt_match(dt_root, compat);
833 if (score > 0 && score < best_score) {
834 best_data = data;
835 best_score = score;
836 }
837 }
838 if (!best_data) {
839 const char *prop;
840 int size;
841
842 pr_err("\n unrecognized device tree list:\n[ ");
843
844 prop = of_get_flat_dt_prop(dt_root, "compatible", &size);
845 if (prop) {
846 while (size > 0) {
847 printk("'%s' ", prop);
848 size -= strlen(prop) + 1;
849 prop += strlen(prop) + 1;
850 }
851 }
852 printk("]\n\n");
853 return NULL;
854 }
855
856 pr_info("Machine model: %s\n", of_flat_dt_get_machine_name());
857
858 return best_data;
859}
860
861#ifdef CONFIG_BLK_DEV_INITRD
862static void __early_init_dt_declare_initrd(unsigned long start,
863 unsigned long end)
864{
865 /* ARM64 would cause a BUG to occur here when CONFIG_DEBUG_VM is
866 * enabled since __va() is called too early. ARM64 does make use
867 * of phys_initrd_start/phys_initrd_size so we can skip this
868 * conversion.
869 */
870 if (!IS_ENABLED(CONFIG_ARM64)) {
871 initrd_start = (unsigned long)__va(start);
872 initrd_end = (unsigned long)__va(end);
873 initrd_below_start_ok = 1;
874 }
875}
876
877/**
878 * early_init_dt_check_for_initrd - Decode initrd location from flat tree
879 * @node: reference to node containing initrd location ('chosen')
880 */
881static void __init early_init_dt_check_for_initrd(unsigned long node)
882{
883 u64 start, end;
884 int len;
885 const __be32 *prop;
886
887 pr_debug("Looking for initrd properties... ");
888
889 prop = of_get_flat_dt_prop(node, "linux,initrd-start", &len);
890 if (!prop)
891 return;
892 start = of_read_number(prop, len/4);
893
894 prop = of_get_flat_dt_prop(node, "linux,initrd-end", &len);
895 if (!prop)
896 return;
897 end = of_read_number(prop, len/4);
898
899 __early_init_dt_declare_initrd(start, end);
900 phys_initrd_start = start;
901 phys_initrd_size = end - start;
902
903 pr_debug("initrd_start=0x%llx initrd_end=0x%llx\n", start, end);
904}
905#else
906static inline void early_init_dt_check_for_initrd(unsigned long node)
907{
908}
909#endif /* CONFIG_BLK_DEV_INITRD */
910
911#ifdef CONFIG_SERIAL_EARLYCON
912
913int __init early_init_dt_scan_chosen_stdout(void)
914{
915 int offset;
916 const char *p, *q, *options = NULL;
917 int l;
918 const struct earlycon_id *match;
919 const void *fdt = initial_boot_params;
920
921 offset = fdt_path_offset(fdt, "/chosen");
922 if (offset < 0)
923 offset = fdt_path_offset(fdt, "/chosen@0");
924 if (offset < 0)
925 return -ENOENT;
926
927 p = fdt_getprop(fdt, offset, "stdout-path", &l);
928 if (!p)
929 p = fdt_getprop(fdt, offset, "linux,stdout-path", &l);
930 if (!p || !l)
931 return -ENOENT;
932
933 q = strchrnul(p, ':');
934 if (*q != '\0')
935 options = q + 1;
936 l = q - p;
937
938 /* Get the node specified by stdout-path */
939 offset = fdt_path_offset_namelen(fdt, p, l);
940 if (offset < 0) {
941 pr_warn("earlycon: stdout-path %.*s not found\n", l, p);
942 return 0;
943 }
944
945 for (match = __earlycon_table; match < __earlycon_table_end; match++) {
946 if (!match->compatible[0])
947 continue;
948
949 if (fdt_node_check_compatible(fdt, offset, match->compatible))
950 continue;
951
952 if (of_setup_earlycon(match, offset, options) == 0)
953 return 0;
954 }
955 return -ENODEV;
956}
957#endif
958
959/*
960 * early_init_dt_scan_root - fetch the top level address and size cells
961 */
962int __init early_init_dt_scan_root(unsigned long node, const char *uname,
963 int depth, void *data)
964{
965 const __be32 *prop;
966
967 if (depth != 0)
968 return 0;
969
970 dt_root_size_cells = OF_ROOT_NODE_SIZE_CELLS_DEFAULT;
971 dt_root_addr_cells = OF_ROOT_NODE_ADDR_CELLS_DEFAULT;
972
973 prop = of_get_flat_dt_prop(node, "#size-cells", NULL);
974 if (prop)
975 dt_root_size_cells = be32_to_cpup(prop);
976 pr_debug("dt_root_size_cells = %x\n", dt_root_size_cells);
977
978 prop = of_get_flat_dt_prop(node, "#address-cells", NULL);
979 if (prop)
980 dt_root_addr_cells = be32_to_cpup(prop);
981 pr_debug("dt_root_addr_cells = %x\n", dt_root_addr_cells);
982
983 /* break now */
984 return 1;
985}
986
987u64 __init dt_mem_next_cell(int s, const __be32 **cellp)
988{
989 const __be32 *p = *cellp;
990
991 *cellp = p + s;
992 return of_read_number(p, s);
993}
994
995/*
996 * early_init_dt_scan_memory - Look for and parse memory nodes
997 */
998int __init early_init_dt_scan_memory(unsigned long node, const char *uname,
999 int depth, void *data)
1000{
1001 const char *type = of_get_flat_dt_prop(node, "device_type", NULL);
1002 const __be32 *reg, *endp;
1003 int l;
1004 bool hotpluggable;
1005
1006 /* We are scanning "memory" nodes only */
1007 if (type == NULL || strcmp(type, "memory") != 0)
1008 return 0;
1009
1010 reg = of_get_flat_dt_prop(node, "linux,usable-memory", &l);
1011 if (reg == NULL)
1012 reg = of_get_flat_dt_prop(node, "reg", &l);
1013 if (reg == NULL)
1014 return 0;
1015
1016 endp = reg + (l / sizeof(__be32));
1017 hotpluggable = of_get_flat_dt_prop(node, "hotpluggable", NULL);
1018
1019 pr_debug("memory scan node %s, reg size %d,\n", uname, l);
1020
1021 while ((endp - reg) >= (dt_root_addr_cells + dt_root_size_cells)) {
1022 u64 base, size;
1023
1024 base = dt_mem_next_cell(dt_root_addr_cells, ®);
1025 size = dt_mem_next_cell(dt_root_size_cells, ®);
1026
1027 if (size == 0)
1028 continue;
1029 pr_debug(" - %llx, %llx\n", base, size);
1030
1031 early_init_dt_add_memory_arch(base, size);
1032
1033 if (!hotpluggable)
1034 continue;
1035
1036 if (early_init_dt_mark_hotplug_memory_arch(base, size))
1037 pr_warn("failed to mark hotplug range 0x%llx - 0x%llx\n",
1038 base, base + size);
1039 }
1040
1041 return 0;
1042}
1043
1044int __init early_init_dt_scan_chosen(unsigned long node, const char *uname,
1045 int depth, void *data)
1046{
1047 int l;
1048 const char *p;
1049 const void *rng_seed;
1050
1051 pr_debug("search \"chosen\", depth: %d, uname: %s\n", depth, uname);
1052
1053 if (depth != 1 || !data ||
1054 (strcmp(uname, "chosen") != 0 && strcmp(uname, "chosen@0") != 0))
1055 return 0;
1056
1057 early_init_dt_check_for_initrd(node);
1058
1059 /* Retrieve command line */
1060 p = of_get_flat_dt_prop(node, "bootargs", &l);
1061 if (p != NULL && l > 0)
1062 strlcpy(data, p, min(l, COMMAND_LINE_SIZE));
1063
1064 /*
1065 * CONFIG_CMDLINE is meant to be a default in case nothing else
1066 * managed to set the command line, unless CONFIG_CMDLINE_FORCE
1067 * is set in which case we override whatever was found earlier.
1068 */
1069#ifdef CONFIG_CMDLINE
1070#if defined(CONFIG_CMDLINE_EXTEND)
1071 strlcat(data, " ", COMMAND_LINE_SIZE);
1072 strlcat(data, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
1073#elif defined(CONFIG_CMDLINE_FORCE)
1074 strlcpy(data, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
1075#else
1076 /* No arguments from boot loader, use kernel's cmdl*/
1077 if (!((char *)data)[0])
1078 strlcpy(data, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
1079#endif
1080#endif /* CONFIG_CMDLINE */
1081
1082 pr_debug("Command line is: %s\n", (char *)data);
1083
1084 rng_seed = of_get_flat_dt_prop(node, "rng-seed", &l);
1085 if (rng_seed && l > 0) {
1086 add_bootloader_randomness(rng_seed, l);
1087
1088 /* try to clear seed so it won't be found. */
1089 fdt_nop_property(initial_boot_params, node, "rng-seed");
1090
1091 /* update CRC check value */
1092 of_fdt_crc32 = crc32_be(~0, initial_boot_params,
1093 fdt_totalsize(initial_boot_params));
1094 }
1095
1096 /* break now */
1097 return 1;
1098}
1099
1100#ifndef MIN_MEMBLOCK_ADDR
1101#define MIN_MEMBLOCK_ADDR __pa(PAGE_OFFSET)
1102#endif
1103#ifndef MAX_MEMBLOCK_ADDR
1104#define MAX_MEMBLOCK_ADDR ((phys_addr_t)~0)
1105#endif
1106
1107void __init __weak early_init_dt_add_memory_arch(u64 base, u64 size)
1108{
1109 const u64 phys_offset = MIN_MEMBLOCK_ADDR;
1110
1111 if (size < PAGE_SIZE - (base & ~PAGE_MASK)) {
1112 pr_warn("Ignoring memory block 0x%llx - 0x%llx\n",
1113 base, base + size);
1114 return;
1115 }
1116
1117 if (!PAGE_ALIGNED(base)) {
1118 size -= PAGE_SIZE - (base & ~PAGE_MASK);
1119 base = PAGE_ALIGN(base);
1120 }
1121 size &= PAGE_MASK;
1122
1123 if (base > MAX_MEMBLOCK_ADDR) {
1124 pr_warn("Ignoring memory block 0x%llx - 0x%llx\n",
1125 base, base + size);
1126 return;
1127 }
1128
1129 if (base + size - 1 > MAX_MEMBLOCK_ADDR) {
1130 pr_warn("Ignoring memory range 0x%llx - 0x%llx\n",
1131 ((u64)MAX_MEMBLOCK_ADDR) + 1, base + size);
1132 size = MAX_MEMBLOCK_ADDR - base + 1;
1133 }
1134
1135 if (base + size < phys_offset) {
1136 pr_warn("Ignoring memory block 0x%llx - 0x%llx\n",
1137 base, base + size);
1138 return;
1139 }
1140 if (base < phys_offset) {
1141 pr_warn("Ignoring memory range 0x%llx - 0x%llx\n",
1142 base, phys_offset);
1143 size -= phys_offset - base;
1144 base = phys_offset;
1145 }
1146 memblock_add(base, size);
1147}
1148
1149int __init __weak early_init_dt_mark_hotplug_memory_arch(u64 base, u64 size)
1150{
1151 return memblock_mark_hotplug(base, size);
1152}
1153
1154int __init __weak early_init_dt_reserve_memory_arch(phys_addr_t base,
1155 phys_addr_t size, bool nomap)
1156{
1157 if (nomap) {
1158 /*
1159 * If the memory is already reserved (by another region), we
1160 * should not allow it to be marked nomap.
1161 */
1162 if (memblock_is_region_reserved(base, size))
1163 return -EBUSY;
1164
1165 return memblock_mark_nomap(base, size);
1166 }
1167 return memblock_reserve(base, size);
1168}
1169
1170static void * __init early_init_dt_alloc_memory_arch(u64 size, u64 align)
1171{
1172 void *ptr = memblock_alloc(size, align);
1173
1174 if (!ptr)
1175 panic("%s: Failed to allocate %llu bytes align=0x%llx\n",
1176 __func__, size, align);
1177
1178 return ptr;
1179}
1180
1181bool __init early_init_dt_verify(void *params)
1182{
1183 if (!params)
1184 return false;
1185
1186 /* check device tree validity */
1187 if (fdt_check_header(params))
1188 return false;
1189
1190 /* Setup flat device-tree pointer */
1191 initial_boot_params = params;
1192 of_fdt_crc32 = crc32_be(~0, initial_boot_params,
1193 fdt_totalsize(initial_boot_params));
1194 return true;
1195}
1196
1197
1198void __init early_init_dt_scan_nodes(void)
1199{
1200 int rc = 0;
1201
1202 /* Retrieve various information from the /chosen node */
1203 rc = of_scan_flat_dt(early_init_dt_scan_chosen, boot_command_line);
1204 if (!rc)
1205 pr_warn("No chosen node found, continuing without\n");
1206
1207 /* Initialize {size,address}-cells info */
1208 of_scan_flat_dt(early_init_dt_scan_root, NULL);
1209
1210 /* Setup memory, calling early_init_dt_add_memory_arch */
1211 of_scan_flat_dt(early_init_dt_scan_memory, NULL);
1212}
1213
1214bool __init early_init_dt_scan(void *params)
1215{
1216 bool status;
1217
1218 status = early_init_dt_verify(params);
1219 if (!status)
1220 return false;
1221
1222 early_init_dt_scan_nodes();
1223 return true;
1224}
1225
1226/**
1227 * unflatten_device_tree - create tree of device_nodes from flat blob
1228 *
1229 * unflattens the device-tree passed by the firmware, creating the
1230 * tree of struct device_node. It also fills the "name" and "type"
1231 * pointers of the nodes so the normal device-tree walking functions
1232 * can be used.
1233 */
1234void __init unflatten_device_tree(void)
1235{
1236 __unflatten_device_tree(initial_boot_params, NULL, &of_root,
1237 early_init_dt_alloc_memory_arch, false);
1238
1239 /* Get pointer to "/chosen" and "/aliases" nodes for use everywhere */
1240 of_alias_scan(early_init_dt_alloc_memory_arch);
1241
1242 unittest_unflatten_overlay_base();
1243}
1244
1245/**
1246 * unflatten_and_copy_device_tree - copy and create tree of device_nodes from flat blob
1247 *
1248 * Copies and unflattens the device-tree passed by the firmware, creating the
1249 * tree of struct device_node. It also fills the "name" and "type"
1250 * pointers of the nodes so the normal device-tree walking functions
1251 * can be used. This should only be used when the FDT memory has not been
1252 * reserved such is the case when the FDT is built-in to the kernel init
1253 * section. If the FDT memory is reserved already then unflatten_device_tree
1254 * should be used instead.
1255 */
1256void __init unflatten_and_copy_device_tree(void)
1257{
1258 int size;
1259 void *dt;
1260
1261 if (!initial_boot_params) {
1262 pr_warn("No valid device tree found, continuing without\n");
1263 return;
1264 }
1265
1266 size = fdt_totalsize(initial_boot_params);
1267 dt = early_init_dt_alloc_memory_arch(size,
1268 roundup_pow_of_two(FDT_V17_SIZE));
1269
1270 if (dt) {
1271 memcpy(dt, initial_boot_params, size);
1272 initial_boot_params = dt;
1273 }
1274 unflatten_device_tree();
1275}
1276
1277#ifdef CONFIG_SYSFS
1278static ssize_t of_fdt_raw_read(struct file *filp, struct kobject *kobj,
1279 struct bin_attribute *bin_attr,
1280 char *buf, loff_t off, size_t count)
1281{
1282 memcpy(buf, initial_boot_params + off, count);
1283 return count;
1284}
1285
1286static int __init of_fdt_raw_init(void)
1287{
1288 static struct bin_attribute of_fdt_raw_attr =
1289 __BIN_ATTR(fdt, S_IRUSR, of_fdt_raw_read, NULL, 0);
1290
1291 if (!initial_boot_params)
1292 return 0;
1293
1294 if (of_fdt_crc32 != crc32_be(~0, initial_boot_params,
1295 fdt_totalsize(initial_boot_params))) {
1296 pr_warn("not creating '/sys/firmware/fdt': CRC check failed\n");
1297 return 0;
1298 }
1299 of_fdt_raw_attr.size = fdt_totalsize(initial_boot_params);
1300 return sysfs_create_bin_file(firmware_kobj, &of_fdt_raw_attr);
1301}
1302late_initcall(of_fdt_raw_init);
1303#endif
1304
1305#endif /* CONFIG_OF_EARLY_FLATTREE */