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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 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_warning("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 * res_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 if (*pathp == '/')
647 pathp = kbasename(pathp);
648 rc = it(offset, pathp, depth, data);
649 }
650 return rc;
651}
652
653/**
654 * of_scan_flat_dt_subnodes - scan sub-nodes of a node call callback on each.
655 * @it: callback function
656 * @data: context data pointer
657 *
658 * This function is used to scan sub-nodes of a node.
659 */
660int __init of_scan_flat_dt_subnodes(unsigned long parent,
661 int (*it)(unsigned long node,
662 const char *uname,
663 void *data),
664 void *data)
665{
666 const void *blob = initial_boot_params;
667 int node;
668
669 fdt_for_each_subnode(node, blob, parent) {
670 const char *pathp;
671 int rc;
672
673 pathp = fdt_get_name(blob, node, NULL);
674 if (*pathp == '/')
675 pathp = kbasename(pathp);
676 rc = it(node, pathp, data);
677 if (rc)
678 return rc;
679 }
680 return 0;
681}
682
683/**
684 * of_get_flat_dt_subnode_by_name - get the subnode by given name
685 *
686 * @node: the parent node
687 * @uname: the name of subnode
688 * @return offset of the subnode, or -FDT_ERR_NOTFOUND if there is none
689 */
690
691int __init of_get_flat_dt_subnode_by_name(unsigned long node, const char *uname)
692{
693 return fdt_subnode_offset(initial_boot_params, node, uname);
694}
695
696/**
697 * of_get_flat_dt_root - find the root node in the flat blob
698 */
699unsigned long __init of_get_flat_dt_root(void)
700{
701 return 0;
702}
703
704/**
705 * of_get_flat_dt_prop - Given a node in the flat blob, return the property ptr
706 *
707 * This function can be used within scan_flattened_dt callback to get
708 * access to properties
709 */
710const void *__init of_get_flat_dt_prop(unsigned long node, const char *name,
711 int *size)
712{
713 return fdt_getprop(initial_boot_params, node, name, size);
714}
715
716/**
717 * of_fdt_is_compatible - Return true if given node from the given blob has
718 * compat in its compatible list
719 * @blob: A device tree blob
720 * @node: node to test
721 * @compat: compatible string to compare with compatible list.
722 *
723 * On match, returns a non-zero value with smaller values returned for more
724 * specific compatible values.
725 */
726static int of_fdt_is_compatible(const void *blob,
727 unsigned long node, const char *compat)
728{
729 const char *cp;
730 int cplen;
731 unsigned long l, score = 0;
732
733 cp = fdt_getprop(blob, node, "compatible", &cplen);
734 if (cp == NULL)
735 return 0;
736 while (cplen > 0) {
737 score++;
738 if (of_compat_cmp(cp, compat, strlen(compat)) == 0)
739 return score;
740 l = strlen(cp) + 1;
741 cp += l;
742 cplen -= l;
743 }
744
745 return 0;
746}
747
748/**
749 * of_flat_dt_is_compatible - Return true if given node has compat in compatible list
750 * @node: node to test
751 * @compat: compatible string to compare with compatible list.
752 */
753int __init of_flat_dt_is_compatible(unsigned long node, const char *compat)
754{
755 return of_fdt_is_compatible(initial_boot_params, node, compat);
756}
757
758/**
759 * of_flat_dt_match - Return true if node matches a list of compatible values
760 */
761static int __init of_flat_dt_match(unsigned long node, const char *const *compat)
762{
763 unsigned int tmp, score = 0;
764
765 if (!compat)
766 return 0;
767
768 while (*compat) {
769 tmp = of_fdt_is_compatible(initial_boot_params, node, *compat);
770 if (tmp && (score == 0 || (tmp < score)))
771 score = tmp;
772 compat++;
773 }
774
775 return score;
776}
777
778/**
779 * of_get_flat_dt_prop - Given a node in the flat blob, return the phandle
780 */
781uint32_t __init of_get_flat_dt_phandle(unsigned long node)
782{
783 return fdt_get_phandle(initial_boot_params, node);
784}
785
786struct fdt_scan_status {
787 const char *name;
788 int namelen;
789 int depth;
790 int found;
791 int (*iterator)(unsigned long node, const char *uname, int depth, void *data);
792 void *data;
793};
794
795const char * __init of_flat_dt_get_machine_name(void)
796{
797 const char *name;
798 unsigned long dt_root = of_get_flat_dt_root();
799
800 name = of_get_flat_dt_prop(dt_root, "model", NULL);
801 if (!name)
802 name = of_get_flat_dt_prop(dt_root, "compatible", NULL);
803 return name;
804}
805
806/**
807 * of_flat_dt_match_machine - Iterate match tables to find matching machine.
808 *
809 * @default_match: A machine specific ptr to return in case of no match.
810 * @get_next_compat: callback function to return next compatible match table.
811 *
812 * Iterate through machine match tables to find the best match for the machine
813 * compatible string in the FDT.
814 */
815const void * __init of_flat_dt_match_machine(const void *default_match,
816 const void * (*get_next_compat)(const char * const**))
817{
818 const void *data = NULL;
819 const void *best_data = default_match;
820 const char *const *compat;
821 unsigned long dt_root;
822 unsigned int best_score = ~1, score = 0;
823
824 dt_root = of_get_flat_dt_root();
825 while ((data = get_next_compat(&compat))) {
826 score = of_flat_dt_match(dt_root, compat);
827 if (score > 0 && score < best_score) {
828 best_data = data;
829 best_score = score;
830 }
831 }
832 if (!best_data) {
833 const char *prop;
834 int size;
835
836 pr_err("\n unrecognized device tree list:\n[ ");
837
838 prop = of_get_flat_dt_prop(dt_root, "compatible", &size);
839 if (prop) {
840 while (size > 0) {
841 printk("'%s' ", prop);
842 size -= strlen(prop) + 1;
843 prop += strlen(prop) + 1;
844 }
845 }
846 printk("]\n\n");
847 return NULL;
848 }
849
850 pr_info("Machine model: %s\n", of_flat_dt_get_machine_name());
851
852 return best_data;
853}
854
855#ifdef CONFIG_BLK_DEV_INITRD
856static void __early_init_dt_declare_initrd(unsigned long start,
857 unsigned long end)
858{
859 /* ARM64 would cause a BUG to occur here when CONFIG_DEBUG_VM is
860 * enabled since __va() is called too early. ARM64 does make use
861 * of phys_initrd_start/phys_initrd_size so we can skip this
862 * conversion.
863 */
864 if (!IS_ENABLED(CONFIG_ARM64)) {
865 initrd_start = (unsigned long)__va(start);
866 initrd_end = (unsigned long)__va(end);
867 initrd_below_start_ok = 1;
868 }
869}
870
871/**
872 * early_init_dt_check_for_initrd - Decode initrd location from flat tree
873 * @node: reference to node containing initrd location ('chosen')
874 */
875static void __init early_init_dt_check_for_initrd(unsigned long node)
876{
877 u64 start, end;
878 int len;
879 const __be32 *prop;
880
881 pr_debug("Looking for initrd properties... ");
882
883 prop = of_get_flat_dt_prop(node, "linux,initrd-start", &len);
884 if (!prop)
885 return;
886 start = of_read_number(prop, len/4);
887
888 prop = of_get_flat_dt_prop(node, "linux,initrd-end", &len);
889 if (!prop)
890 return;
891 end = of_read_number(prop, len/4);
892
893 __early_init_dt_declare_initrd(start, end);
894 phys_initrd_start = start;
895 phys_initrd_size = end - start;
896
897 pr_debug("initrd_start=0x%llx initrd_end=0x%llx\n",
898 (unsigned long long)start, (unsigned long long)end);
899}
900#else
901static inline void early_init_dt_check_for_initrd(unsigned long node)
902{
903}
904#endif /* CONFIG_BLK_DEV_INITRD */
905
906#ifdef CONFIG_SERIAL_EARLYCON
907
908int __init early_init_dt_scan_chosen_stdout(void)
909{
910 int offset;
911 const char *p, *q, *options = NULL;
912 int l;
913 const struct earlycon_id **p_match;
914 const void *fdt = initial_boot_params;
915
916 offset = fdt_path_offset(fdt, "/chosen");
917 if (offset < 0)
918 offset = fdt_path_offset(fdt, "/chosen@0");
919 if (offset < 0)
920 return -ENOENT;
921
922 p = fdt_getprop(fdt, offset, "stdout-path", &l);
923 if (!p)
924 p = fdt_getprop(fdt, offset, "linux,stdout-path", &l);
925 if (!p || !l)
926 return -ENOENT;
927
928 q = strchrnul(p, ':');
929 if (*q != '\0')
930 options = q + 1;
931 l = q - p;
932
933 /* Get the node specified by stdout-path */
934 offset = fdt_path_offset_namelen(fdt, p, l);
935 if (offset < 0) {
936 pr_warn("earlycon: stdout-path %.*s not found\n", l, p);
937 return 0;
938 }
939
940 for (p_match = __earlycon_table; p_match < __earlycon_table_end;
941 p_match++) {
942 const struct earlycon_id *match = *p_match;
943
944 if (!match->compatible[0])
945 continue;
946
947 if (fdt_node_check_compatible(fdt, offset, match->compatible))
948 continue;
949
950 of_setup_earlycon(match, offset, options);
951 return 0;
952 }
953 return -ENODEV;
954}
955#endif
956
957/**
958 * early_init_dt_scan_root - fetch the top level address and size cells
959 */
960int __init early_init_dt_scan_root(unsigned long node, const char *uname,
961 int depth, void *data)
962{
963 const __be32 *prop;
964
965 if (depth != 0)
966 return 0;
967
968 dt_root_size_cells = OF_ROOT_NODE_SIZE_CELLS_DEFAULT;
969 dt_root_addr_cells = OF_ROOT_NODE_ADDR_CELLS_DEFAULT;
970
971 prop = of_get_flat_dt_prop(node, "#size-cells", NULL);
972 if (prop)
973 dt_root_size_cells = be32_to_cpup(prop);
974 pr_debug("dt_root_size_cells = %x\n", dt_root_size_cells);
975
976 prop = of_get_flat_dt_prop(node, "#address-cells", NULL);
977 if (prop)
978 dt_root_addr_cells = be32_to_cpup(prop);
979 pr_debug("dt_root_addr_cells = %x\n", dt_root_addr_cells);
980
981 /* break now */
982 return 1;
983}
984
985u64 __init dt_mem_next_cell(int s, const __be32 **cellp)
986{
987 const __be32 *p = *cellp;
988
989 *cellp = p + s;
990 return of_read_number(p, s);
991}
992
993/**
994 * early_init_dt_scan_memory - Look for and parse memory nodes
995 */
996int __init early_init_dt_scan_memory(unsigned long node, const char *uname,
997 int depth, void *data)
998{
999 const char *type = of_get_flat_dt_prop(node, "device_type", NULL);
1000 const __be32 *reg, *endp;
1001 int l;
1002 bool hotpluggable;
1003
1004 /* We are scanning "memory" nodes only */
1005 if (type == NULL || strcmp(type, "memory") != 0)
1006 return 0;
1007
1008 reg = of_get_flat_dt_prop(node, "linux,usable-memory", &l);
1009 if (reg == NULL)
1010 reg = of_get_flat_dt_prop(node, "reg", &l);
1011 if (reg == NULL)
1012 return 0;
1013
1014 endp = reg + (l / sizeof(__be32));
1015 hotpluggable = of_get_flat_dt_prop(node, "hotpluggable", NULL);
1016
1017 pr_debug("memory scan node %s, reg size %d,\n", uname, l);
1018
1019 while ((endp - reg) >= (dt_root_addr_cells + dt_root_size_cells)) {
1020 u64 base, size;
1021
1022 base = dt_mem_next_cell(dt_root_addr_cells, ®);
1023 size = dt_mem_next_cell(dt_root_size_cells, ®);
1024
1025 if (size == 0)
1026 continue;
1027 pr_debug(" - %llx , %llx\n", (unsigned long long)base,
1028 (unsigned long long)size);
1029
1030 early_init_dt_add_memory_arch(base, size);
1031
1032 if (!hotpluggable)
1033 continue;
1034
1035 if (early_init_dt_mark_hotplug_memory_arch(base, size))
1036 pr_warn("failed to mark hotplug range 0x%llx - 0x%llx\n",
1037 base, base + size);
1038 }
1039
1040 return 0;
1041}
1042
1043int __init early_init_dt_scan_chosen(unsigned long node, const char *uname,
1044 int depth, void *data)
1045{
1046 int l;
1047 const char *p;
1048 const void *rng_seed;
1049
1050 pr_debug("search \"chosen\", depth: %d, uname: %s\n", depth, uname);
1051
1052 if (depth != 1 || !data ||
1053 (strcmp(uname, "chosen") != 0 && strcmp(uname, "chosen@0") != 0))
1054 return 0;
1055
1056 early_init_dt_check_for_initrd(node);
1057
1058 /* Retrieve command line */
1059 p = of_get_flat_dt_prop(node, "bootargs", &l);
1060 if (p != NULL && l > 0)
1061 strlcpy(data, p, min(l, COMMAND_LINE_SIZE));
1062
1063 /*
1064 * CONFIG_CMDLINE is meant to be a default in case nothing else
1065 * managed to set the command line, unless CONFIG_CMDLINE_FORCE
1066 * is set in which case we override whatever was found earlier.
1067 */
1068#ifdef CONFIG_CMDLINE
1069#if defined(CONFIG_CMDLINE_EXTEND)
1070 strlcat(data, " ", COMMAND_LINE_SIZE);
1071 strlcat(data, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
1072#elif defined(CONFIG_CMDLINE_FORCE)
1073 strlcpy(data, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
1074#else
1075 /* No arguments from boot loader, use kernel's cmdl*/
1076 if (!((char *)data)[0])
1077 strlcpy(data, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
1078#endif
1079#endif /* CONFIG_CMDLINE */
1080
1081 pr_debug("Command line is: %s\n", (char*)data);
1082
1083 rng_seed = of_get_flat_dt_prop(node, "rng-seed", &l);
1084 if (rng_seed && l > 0) {
1085 add_bootloader_randomness(rng_seed, l);
1086
1087 /* try to clear seed so it won't be found. */
1088 fdt_nop_property(initial_boot_params, node, "rng-seed");
1089
1090 /* update CRC check value */
1091 of_fdt_crc32 = crc32_be(~0, initial_boot_params,
1092 fdt_totalsize(initial_boot_params));
1093 }
1094
1095 /* break now */
1096 return 1;
1097}
1098
1099#ifndef MIN_MEMBLOCK_ADDR
1100#define MIN_MEMBLOCK_ADDR __pa(PAGE_OFFSET)
1101#endif
1102#ifndef MAX_MEMBLOCK_ADDR
1103#define MAX_MEMBLOCK_ADDR ((phys_addr_t)~0)
1104#endif
1105
1106void __init __weak early_init_dt_add_memory_arch(u64 base, u64 size)
1107{
1108 const u64 phys_offset = MIN_MEMBLOCK_ADDR;
1109
1110 if (size < PAGE_SIZE - (base & ~PAGE_MASK)) {
1111 pr_warn("Ignoring memory block 0x%llx - 0x%llx\n",
1112 base, base + size);
1113 return;
1114 }
1115
1116 if (!PAGE_ALIGNED(base)) {
1117 size -= PAGE_SIZE - (base & ~PAGE_MASK);
1118 base = PAGE_ALIGN(base);
1119 }
1120 size &= PAGE_MASK;
1121
1122 if (base > MAX_MEMBLOCK_ADDR) {
1123 pr_warning("Ignoring memory block 0x%llx - 0x%llx\n",
1124 base, base + size);
1125 return;
1126 }
1127
1128 if (base + size - 1 > MAX_MEMBLOCK_ADDR) {
1129 pr_warning("Ignoring memory range 0x%llx - 0x%llx\n",
1130 ((u64)MAX_MEMBLOCK_ADDR) + 1, base + size);
1131 size = MAX_MEMBLOCK_ADDR - base + 1;
1132 }
1133
1134 if (base + size < phys_offset) {
1135 pr_warning("Ignoring memory block 0x%llx - 0x%llx\n",
1136 base, base + size);
1137 return;
1138 }
1139 if (base < phys_offset) {
1140 pr_warning("Ignoring memory range 0x%llx - 0x%llx\n",
1141 base, phys_offset);
1142 size -= phys_offset - base;
1143 base = phys_offset;
1144 }
1145 memblock_add(base, size);
1146}
1147
1148int __init __weak early_init_dt_mark_hotplug_memory_arch(u64 base, u64 size)
1149{
1150 return memblock_mark_hotplug(base, size);
1151}
1152
1153int __init __weak early_init_dt_reserve_memory_arch(phys_addr_t base,
1154 phys_addr_t size, bool nomap)
1155{
1156 if (nomap)
1157 return memblock_remove(base, size);
1158 return memblock_reserve(base, size);
1159}
1160
1161static void * __init early_init_dt_alloc_memory_arch(u64 size, u64 align)
1162{
1163 void *ptr = memblock_alloc(size, align);
1164
1165 if (!ptr)
1166 panic("%s: Failed to allocate %llu bytes align=0x%llx\n",
1167 __func__, size, align);
1168
1169 return ptr;
1170}
1171
1172bool __init early_init_dt_verify(void *params)
1173{
1174 if (!params)
1175 return false;
1176
1177 /* check device tree validity */
1178 if (fdt_check_header(params))
1179 return false;
1180
1181 /* Setup flat device-tree pointer */
1182 initial_boot_params = params;
1183 of_fdt_crc32 = crc32_be(~0, initial_boot_params,
1184 fdt_totalsize(initial_boot_params));
1185 return true;
1186}
1187
1188
1189void __init early_init_dt_scan_nodes(void)
1190{
1191 int rc = 0;
1192
1193 /* Retrieve various information from the /chosen node */
1194 rc = of_scan_flat_dt(early_init_dt_scan_chosen, boot_command_line);
1195 if (!rc)
1196 pr_warn("No chosen node found, continuing without\n");
1197
1198 /* Initialize {size,address}-cells info */
1199 of_scan_flat_dt(early_init_dt_scan_root, NULL);
1200
1201 /* Setup memory, calling early_init_dt_add_memory_arch */
1202 of_scan_flat_dt(early_init_dt_scan_memory, NULL);
1203}
1204
1205bool __init early_init_dt_scan(void *params)
1206{
1207 bool status;
1208
1209 status = early_init_dt_verify(params);
1210 if (!status)
1211 return false;
1212
1213 early_init_dt_scan_nodes();
1214 return true;
1215}
1216
1217/**
1218 * unflatten_device_tree - create tree of device_nodes from flat blob
1219 *
1220 * unflattens the device-tree passed by the firmware, creating the
1221 * tree of struct device_node. It also fills the "name" and "type"
1222 * pointers of the nodes so the normal device-tree walking functions
1223 * can be used.
1224 */
1225void __init unflatten_device_tree(void)
1226{
1227 __unflatten_device_tree(initial_boot_params, NULL, &of_root,
1228 early_init_dt_alloc_memory_arch, false);
1229
1230 /* Get pointer to "/chosen" and "/aliases" nodes for use everywhere */
1231 of_alias_scan(early_init_dt_alloc_memory_arch);
1232
1233 unittest_unflatten_overlay_base();
1234}
1235
1236/**
1237 * unflatten_and_copy_device_tree - copy and create tree of device_nodes from flat blob
1238 *
1239 * Copies and unflattens the device-tree passed by the firmware, creating the
1240 * tree of struct device_node. It also fills the "name" and "type"
1241 * pointers of the nodes so the normal device-tree walking functions
1242 * can be used. This should only be used when the FDT memory has not been
1243 * reserved such is the case when the FDT is built-in to the kernel init
1244 * section. If the FDT memory is reserved already then unflatten_device_tree
1245 * should be used instead.
1246 */
1247void __init unflatten_and_copy_device_tree(void)
1248{
1249 int size;
1250 void *dt;
1251
1252 if (!initial_boot_params) {
1253 pr_warn("No valid device tree found, continuing without\n");
1254 return;
1255 }
1256
1257 size = fdt_totalsize(initial_boot_params);
1258 dt = early_init_dt_alloc_memory_arch(size,
1259 roundup_pow_of_two(FDT_V17_SIZE));
1260
1261 if (dt) {
1262 memcpy(dt, initial_boot_params, size);
1263 initial_boot_params = dt;
1264 }
1265 unflatten_device_tree();
1266}
1267
1268#ifdef CONFIG_SYSFS
1269static ssize_t of_fdt_raw_read(struct file *filp, struct kobject *kobj,
1270 struct bin_attribute *bin_attr,
1271 char *buf, loff_t off, size_t count)
1272{
1273 memcpy(buf, initial_boot_params + off, count);
1274 return count;
1275}
1276
1277static int __init of_fdt_raw_init(void)
1278{
1279 static struct bin_attribute of_fdt_raw_attr =
1280 __BIN_ATTR(fdt, S_IRUSR, of_fdt_raw_read, NULL, 0);
1281
1282 if (!initial_boot_params)
1283 return 0;
1284
1285 if (of_fdt_crc32 != crc32_be(~0, initial_boot_params,
1286 fdt_totalsize(initial_boot_params))) {
1287 pr_warn("not creating '/sys/firmware/fdt': CRC check failed\n");
1288 return 0;
1289 }
1290 of_fdt_raw_attr.size = fdt_totalsize(initial_boot_params);
1291 return sysfs_create_bin_file(firmware_kobj, &of_fdt_raw_attr);
1292}
1293late_initcall(of_fdt_raw_init);
1294#endif
1295
1296#endif /* CONFIG_OF_EARLY_FLATTREE */