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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/crc32.h>
12#include <linux/kernel.h>
13#include <linux/initrd.h>
14#include <linux/memblock.h>
15#include <linux/mutex.h>
16#include <linux/of.h>
17#include <linux/of_fdt.h>
18#include <linux/of_reserved_mem.h>
19#include <linux/sizes.h>
20#include <linux/string.h>
21#include <linux/errno.h>
22#include <linux/slab.h>
23#include <linux/libfdt.h>
24#include <linux/debugfs.h>
25#include <linux/serial_core.h>
26#include <linux/sysfs.h>
27#include <linux/random.h>
28
29#include <asm/setup.h> /* for COMMAND_LINE_SIZE */
30#include <asm/page.h>
31
32#include "of_private.h"
33
34/*
35 * of_fdt_limit_memory - limit the number of regions in the /memory node
36 * @limit: maximum entries
37 *
38 * Adjust the flattened device tree to have at most 'limit' number of
39 * memory entries in the /memory node. This function may be called
40 * any time after initial_boot_param is set.
41 */
42void __init of_fdt_limit_memory(int limit)
43{
44 int memory;
45 int len;
46 const void *val;
47 int nr_address_cells = OF_ROOT_NODE_ADDR_CELLS_DEFAULT;
48 int nr_size_cells = OF_ROOT_NODE_SIZE_CELLS_DEFAULT;
49 const __be32 *addr_prop;
50 const __be32 *size_prop;
51 int root_offset;
52 int cell_size;
53
54 root_offset = fdt_path_offset(initial_boot_params, "/");
55 if (root_offset < 0)
56 return;
57
58 addr_prop = fdt_getprop(initial_boot_params, root_offset,
59 "#address-cells", NULL);
60 if (addr_prop)
61 nr_address_cells = fdt32_to_cpu(*addr_prop);
62
63 size_prop = fdt_getprop(initial_boot_params, root_offset,
64 "#size-cells", NULL);
65 if (size_prop)
66 nr_size_cells = fdt32_to_cpu(*size_prop);
67
68 cell_size = sizeof(uint32_t)*(nr_address_cells + nr_size_cells);
69
70 memory = fdt_path_offset(initial_boot_params, "/memory");
71 if (memory > 0) {
72 val = fdt_getprop(initial_boot_params, memory, "reg", &len);
73 if (len > limit*cell_size) {
74 len = limit*cell_size;
75 pr_debug("Limiting number of entries to %d\n", limit);
76 fdt_setprop(initial_boot_params, memory, "reg", val,
77 len);
78 }
79 }
80}
81
82static bool of_fdt_device_is_available(const void *blob, unsigned long node)
83{
84 const char *status = fdt_getprop(blob, node, "status", NULL);
85
86 if (!status)
87 return true;
88
89 if (!strcmp(status, "ok") || !strcmp(status, "okay"))
90 return true;
91
92 return false;
93}
94
95static void *unflatten_dt_alloc(void **mem, unsigned long size,
96 unsigned long align)
97{
98 void *res;
99
100 *mem = PTR_ALIGN(*mem, align);
101 res = *mem;
102 *mem += size;
103
104 return res;
105}
106
107static void populate_properties(const void *blob,
108 int offset,
109 void **mem,
110 struct device_node *np,
111 const char *nodename,
112 bool dryrun)
113{
114 struct property *pp, **pprev = NULL;
115 int cur;
116 bool has_name = false;
117
118 pprev = &np->properties;
119 for (cur = fdt_first_property_offset(blob, offset);
120 cur >= 0;
121 cur = fdt_next_property_offset(blob, cur)) {
122 const __be32 *val;
123 const char *pname;
124 u32 sz;
125
126 val = fdt_getprop_by_offset(blob, cur, &pname, &sz);
127 if (!val) {
128 pr_warn("Cannot locate property at 0x%x\n", cur);
129 continue;
130 }
131
132 if (!pname) {
133 pr_warn("Cannot find property name at 0x%x\n", cur);
134 continue;
135 }
136
137 if (!strcmp(pname, "name"))
138 has_name = true;
139
140 pp = unflatten_dt_alloc(mem, sizeof(struct property),
141 __alignof__(struct property));
142 if (dryrun)
143 continue;
144
145 /* We accept flattened tree phandles either in
146 * ePAPR-style "phandle" properties, or the
147 * legacy "linux,phandle" properties. If both
148 * appear and have different values, things
149 * will get weird. Don't do that.
150 */
151 if (!strcmp(pname, "phandle") ||
152 !strcmp(pname, "linux,phandle")) {
153 if (!np->phandle)
154 np->phandle = be32_to_cpup(val);
155 }
156
157 /* And we process the "ibm,phandle" property
158 * used in pSeries dynamic device tree
159 * stuff
160 */
161 if (!strcmp(pname, "ibm,phandle"))
162 np->phandle = be32_to_cpup(val);
163
164 pp->name = (char *)pname;
165 pp->length = sz;
166 pp->value = (__be32 *)val;
167 *pprev = pp;
168 pprev = &pp->next;
169 }
170
171 /* With version 0x10 we may not have the name property,
172 * recreate it here from the unit name if absent
173 */
174 if (!has_name) {
175 const char *p = nodename, *ps = p, *pa = NULL;
176 int len;
177
178 while (*p) {
179 if ((*p) == '@')
180 pa = p;
181 else if ((*p) == '/')
182 ps = p + 1;
183 p++;
184 }
185
186 if (pa < ps)
187 pa = p;
188 len = (pa - ps) + 1;
189 pp = unflatten_dt_alloc(mem, sizeof(struct property) + len,
190 __alignof__(struct property));
191 if (!dryrun) {
192 pp->name = "name";
193 pp->length = len;
194 pp->value = pp + 1;
195 *pprev = pp;
196 pprev = &pp->next;
197 memcpy(pp->value, ps, len - 1);
198 ((char *)pp->value)[len - 1] = 0;
199 pr_debug("fixed up name for %s -> %s\n",
200 nodename, (char *)pp->value);
201 }
202 }
203
204 if (!dryrun)
205 *pprev = NULL;
206}
207
208static bool populate_node(const void *blob,
209 int offset,
210 void **mem,
211 struct device_node *dad,
212 struct device_node **pnp,
213 bool dryrun)
214{
215 struct device_node *np;
216 const char *pathp;
217 unsigned int l, allocl;
218
219 pathp = fdt_get_name(blob, offset, &l);
220 if (!pathp) {
221 *pnp = NULL;
222 return false;
223 }
224
225 allocl = ++l;
226
227 np = unflatten_dt_alloc(mem, sizeof(struct device_node) + allocl,
228 __alignof__(struct device_node));
229 if (!dryrun) {
230 char *fn;
231 of_node_init(np);
232 np->full_name = fn = ((char *)np) + sizeof(*np);
233
234 memcpy(fn, pathp, l);
235
236 if (dad != NULL) {
237 np->parent = dad;
238 np->sibling = dad->child;
239 dad->child = np;
240 }
241 }
242
243 populate_properties(blob, offset, mem, np, pathp, dryrun);
244 if (!dryrun) {
245 np->name = of_get_property(np, "name", NULL);
246 if (!np->name)
247 np->name = "<NULL>";
248 }
249
250 *pnp = np;
251 return true;
252}
253
254static void reverse_nodes(struct device_node *parent)
255{
256 struct device_node *child, *next;
257
258 /* In-depth first */
259 child = parent->child;
260 while (child) {
261 reverse_nodes(child);
262
263 child = child->sibling;
264 }
265
266 /* Reverse the nodes in the child list */
267 child = parent->child;
268 parent->child = NULL;
269 while (child) {
270 next = child->sibling;
271
272 child->sibling = parent->child;
273 parent->child = child;
274 child = next;
275 }
276}
277
278/**
279 * unflatten_dt_nodes - Alloc and populate a device_node from the flat tree
280 * @blob: The parent device tree blob
281 * @mem: Memory chunk to use for allocating device nodes and properties
282 * @dad: Parent struct device_node
283 * @nodepp: The device_node tree created by the call
284 *
285 * It returns the size of unflattened device tree or error code
286 */
287static int unflatten_dt_nodes(const void *blob,
288 void *mem,
289 struct device_node *dad,
290 struct device_node **nodepp)
291{
292 struct device_node *root;
293 int offset = 0, depth = 0, initial_depth = 0;
294#define FDT_MAX_DEPTH 64
295 struct device_node *nps[FDT_MAX_DEPTH];
296 void *base = mem;
297 bool dryrun = !base;
298
299 if (nodepp)
300 *nodepp = NULL;
301
302 /*
303 * We're unflattening device sub-tree if @dad is valid. There are
304 * possibly multiple nodes in the first level of depth. We need
305 * set @depth to 1 to make fdt_next_node() happy as it bails
306 * immediately when negative @depth is found. Otherwise, the device
307 * nodes except the first one won't be unflattened successfully.
308 */
309 if (dad)
310 depth = initial_depth = 1;
311
312 root = dad;
313 nps[depth] = dad;
314
315 for (offset = 0;
316 offset >= 0 && depth >= initial_depth;
317 offset = fdt_next_node(blob, offset, &depth)) {
318 if (WARN_ON_ONCE(depth >= FDT_MAX_DEPTH))
319 continue;
320
321 if (!IS_ENABLED(CONFIG_OF_KOBJ) &&
322 !of_fdt_device_is_available(blob, offset))
323 continue;
324
325 if (!populate_node(blob, offset, &mem, nps[depth],
326 &nps[depth+1], dryrun))
327 return mem - base;
328
329 if (!dryrun && nodepp && !*nodepp)
330 *nodepp = nps[depth+1];
331 if (!dryrun && !root)
332 root = nps[depth+1];
333 }
334
335 if (offset < 0 && offset != -FDT_ERR_NOTFOUND) {
336 pr_err("Error %d processing FDT\n", offset);
337 return -EINVAL;
338 }
339
340 /*
341 * Reverse the child list. Some drivers assumes node order matches .dts
342 * node order
343 */
344 if (!dryrun)
345 reverse_nodes(root);
346
347 return mem - base;
348}
349
350/**
351 * __unflatten_device_tree - create tree of device_nodes from flat blob
352 *
353 * unflattens a device-tree, creating the
354 * tree of struct device_node. It also fills the "name" and "type"
355 * pointers of the nodes so the normal device-tree walking functions
356 * can be used.
357 * @blob: The blob to expand
358 * @dad: Parent device node
359 * @mynodes: The device_node tree created by the call
360 * @dt_alloc: An allocator that provides a virtual address to memory
361 * for the resulting tree
362 * @detached: if true set OF_DETACHED on @mynodes
363 *
364 * Returns NULL on failure or the memory chunk containing the unflattened
365 * device tree on success.
366 */
367void *__unflatten_device_tree(const void *blob,
368 struct device_node *dad,
369 struct device_node **mynodes,
370 void *(*dt_alloc)(u64 size, u64 align),
371 bool detached)
372{
373 int size;
374 void *mem;
375
376 pr_debug(" -> unflatten_device_tree()\n");
377
378 if (!blob) {
379 pr_debug("No device tree pointer\n");
380 return NULL;
381 }
382
383 pr_debug("Unflattening device tree:\n");
384 pr_debug("magic: %08x\n", fdt_magic(blob));
385 pr_debug("size: %08x\n", fdt_totalsize(blob));
386 pr_debug("version: %08x\n", fdt_version(blob));
387
388 if (fdt_check_header(blob)) {
389 pr_err("Invalid device tree blob header\n");
390 return NULL;
391 }
392
393 /* First pass, scan for size */
394 size = unflatten_dt_nodes(blob, NULL, dad, NULL);
395 if (size < 0)
396 return NULL;
397
398 size = ALIGN(size, 4);
399 pr_debug(" size is %d, allocating...\n", size);
400
401 /* Allocate memory for the expanded device tree */
402 mem = dt_alloc(size + 4, __alignof__(struct device_node));
403 if (!mem)
404 return NULL;
405
406 memset(mem, 0, size);
407
408 *(__be32 *)(mem + size) = cpu_to_be32(0xdeadbeef);
409
410 pr_debug(" unflattening %p...\n", mem);
411
412 /* Second pass, do actual unflattening */
413 unflatten_dt_nodes(blob, mem, dad, mynodes);
414 if (be32_to_cpup(mem + size) != 0xdeadbeef)
415 pr_warn("End of tree marker overwritten: %08x\n",
416 be32_to_cpup(mem + size));
417
418 if (detached && mynodes) {
419 of_node_set_flag(*mynodes, OF_DETACHED);
420 pr_debug("unflattened tree is detached\n");
421 }
422
423 pr_debug(" <- unflatten_device_tree()\n");
424 return mem;
425}
426
427static void *kernel_tree_alloc(u64 size, u64 align)
428{
429 return kzalloc(size, GFP_KERNEL);
430}
431
432static DEFINE_MUTEX(of_fdt_unflatten_mutex);
433
434/**
435 * of_fdt_unflatten_tree - create tree of device_nodes from flat blob
436 * @blob: Flat device tree blob
437 * @dad: Parent device node
438 * @mynodes: The device tree created by the call
439 *
440 * unflattens the device-tree passed by the firmware, creating the
441 * tree of struct device_node. It also fills the "name" and "type"
442 * pointers of the nodes so the normal device-tree walking functions
443 * can be used.
444 *
445 * Returns NULL on failure or the memory chunk containing the unflattened
446 * device tree on success.
447 */
448void *of_fdt_unflatten_tree(const unsigned long *blob,
449 struct device_node *dad,
450 struct device_node **mynodes)
451{
452 void *mem;
453
454 mutex_lock(&of_fdt_unflatten_mutex);
455 mem = __unflatten_device_tree(blob, dad, mynodes, &kernel_tree_alloc,
456 true);
457 mutex_unlock(&of_fdt_unflatten_mutex);
458
459 return mem;
460}
461EXPORT_SYMBOL_GPL(of_fdt_unflatten_tree);
462
463/* Everything below here references initial_boot_params directly. */
464int __initdata dt_root_addr_cells;
465int __initdata dt_root_size_cells;
466
467void *initial_boot_params __ro_after_init;
468
469#ifdef CONFIG_OF_EARLY_FLATTREE
470
471static u32 of_fdt_crc32;
472
473/**
474 * __reserved_mem_reserve_reg() - reserve all memory described in 'reg' property
475 */
476static int __init __reserved_mem_reserve_reg(unsigned long node,
477 const char *uname)
478{
479 int t_len = (dt_root_addr_cells + dt_root_size_cells) * sizeof(__be32);
480 phys_addr_t base, size;
481 int len;
482 const __be32 *prop;
483 int first = 1;
484 bool nomap;
485
486 prop = of_get_flat_dt_prop(node, "reg", &len);
487 if (!prop)
488 return -ENOENT;
489
490 if (len && len % t_len != 0) {
491 pr_err("Reserved memory: invalid reg property in '%s', skipping node.\n",
492 uname);
493 return -EINVAL;
494 }
495
496 nomap = of_get_flat_dt_prop(node, "no-map", NULL) != NULL;
497
498 while (len >= t_len) {
499 base = dt_mem_next_cell(dt_root_addr_cells, &prop);
500 size = dt_mem_next_cell(dt_root_size_cells, &prop);
501
502 if (size &&
503 early_init_dt_reserve_memory_arch(base, size, nomap) == 0)
504 pr_debug("Reserved memory: reserved region for node '%s': base %pa, size %ld MiB\n",
505 uname, &base, (unsigned long)size / SZ_1M);
506 else
507 pr_info("Reserved memory: failed to reserve memory for node '%s': base %pa, size %ld MiB\n",
508 uname, &base, (unsigned long)size / SZ_1M);
509
510 len -= t_len;
511 if (first) {
512 fdt_reserved_mem_save_node(node, uname, base, size);
513 first = 0;
514 }
515 }
516 return 0;
517}
518
519/**
520 * __reserved_mem_check_root() - check if #size-cells, #address-cells provided
521 * in /reserved-memory matches the values supported by the current implementation,
522 * also check if ranges property has been provided
523 */
524static int __init __reserved_mem_check_root(unsigned long node)
525{
526 const __be32 *prop;
527
528 prop = of_get_flat_dt_prop(node, "#size-cells", NULL);
529 if (!prop || be32_to_cpup(prop) != dt_root_size_cells)
530 return -EINVAL;
531
532 prop = of_get_flat_dt_prop(node, "#address-cells", NULL);
533 if (!prop || be32_to_cpup(prop) != dt_root_addr_cells)
534 return -EINVAL;
535
536 prop = of_get_flat_dt_prop(node, "ranges", NULL);
537 if (!prop)
538 return -EINVAL;
539 return 0;
540}
541
542/**
543 * fdt_scan_reserved_mem() - scan a single FDT node for reserved memory
544 */
545static int __init __fdt_scan_reserved_mem(unsigned long node, const char *uname,
546 int depth, void *data)
547{
548 static int found;
549 int err;
550
551 if (!found && depth == 1 && strcmp(uname, "reserved-memory") == 0) {
552 if (__reserved_mem_check_root(node) != 0) {
553 pr_err("Reserved memory: unsupported node format, ignoring\n");
554 /* break scan */
555 return 1;
556 }
557 found = 1;
558 /* scan next node */
559 return 0;
560 } else if (!found) {
561 /* scan next node */
562 return 0;
563 } else if (found && depth < 2) {
564 /* scanning of /reserved-memory has been finished */
565 return 1;
566 }
567
568 if (!of_fdt_device_is_available(initial_boot_params, node))
569 return 0;
570
571 err = __reserved_mem_reserve_reg(node, uname);
572 if (err == -ENOENT && of_get_flat_dt_prop(node, "size", NULL))
573 fdt_reserved_mem_save_node(node, uname, 0, 0);
574
575 /* scan next node */
576 return 0;
577}
578
579/**
580 * early_init_fdt_scan_reserved_mem() - create reserved memory regions
581 *
582 * This function grabs memory from early allocator for device exclusive use
583 * defined in device tree structures. It should be called by arch specific code
584 * once the early allocator (i.e. memblock) has been fully activated.
585 */
586void __init early_init_fdt_scan_reserved_mem(void)
587{
588 int n;
589 u64 base, size;
590
591 if (!initial_boot_params)
592 return;
593
594 /* Process header /memreserve/ fields */
595 for (n = 0; ; n++) {
596 fdt_get_mem_rsv(initial_boot_params, n, &base, &size);
597 if (!size)
598 break;
599 early_init_dt_reserve_memory_arch(base, size, false);
600 }
601
602 of_scan_flat_dt(__fdt_scan_reserved_mem, NULL);
603 fdt_init_reserved_mem();
604}
605
606/**
607 * early_init_fdt_reserve_self() - reserve the memory used by the FDT blob
608 */
609void __init early_init_fdt_reserve_self(void)
610{
611 if (!initial_boot_params)
612 return;
613
614 /* Reserve the dtb region */
615 early_init_dt_reserve_memory_arch(__pa(initial_boot_params),
616 fdt_totalsize(initial_boot_params),
617 false);
618}
619
620/**
621 * of_scan_flat_dt - scan flattened tree blob and call callback on each.
622 * @it: callback function
623 * @data: context data pointer
624 *
625 * This function is used to scan the flattened device-tree, it is
626 * used to extract the memory information at boot before we can
627 * unflatten the tree
628 */
629int __init of_scan_flat_dt(int (*it)(unsigned long node,
630 const char *uname, int depth,
631 void *data),
632 void *data)
633{
634 const void *blob = initial_boot_params;
635 const char *pathp;
636 int offset, rc = 0, depth = -1;
637
638 if (!blob)
639 return 0;
640
641 for (offset = fdt_next_node(blob, -1, &depth);
642 offset >= 0 && depth >= 0 && !rc;
643 offset = fdt_next_node(blob, offset, &depth)) {
644
645 pathp = fdt_get_name(blob, offset, NULL);
646 rc = it(offset, pathp, depth, data);
647 }
648 return rc;
649}
650
651/**
652 * of_scan_flat_dt_subnodes - scan sub-nodes of a node call callback on each.
653 * @it: callback function
654 * @data: context data pointer
655 *
656 * This function is used to scan sub-nodes of a node.
657 */
658int __init of_scan_flat_dt_subnodes(unsigned long parent,
659 int (*it)(unsigned long node,
660 const char *uname,
661 void *data),
662 void *data)
663{
664 const void *blob = initial_boot_params;
665 int node;
666
667 fdt_for_each_subnode(node, blob, parent) {
668 const char *pathp;
669 int rc;
670
671 pathp = fdt_get_name(blob, node, NULL);
672 rc = it(node, pathp, data);
673 if (rc)
674 return rc;
675 }
676 return 0;
677}
678
679/**
680 * of_get_flat_dt_subnode_by_name - get the subnode by given name
681 *
682 * @node: the parent node
683 * @uname: the name of subnode
684 * @return offset of the subnode, or -FDT_ERR_NOTFOUND if there is none
685 */
686
687int __init of_get_flat_dt_subnode_by_name(unsigned long node, const char *uname)
688{
689 return fdt_subnode_offset(initial_boot_params, node, uname);
690}
691
692/**
693 * of_get_flat_dt_root - find the root node in the flat blob
694 */
695unsigned long __init of_get_flat_dt_root(void)
696{
697 return 0;
698}
699
700/**
701 * of_get_flat_dt_prop - Given a node in the flat blob, return the property ptr
702 *
703 * This function can be used within scan_flattened_dt callback to get
704 * access to properties
705 */
706const void *__init of_get_flat_dt_prop(unsigned long node, const char *name,
707 int *size)
708{
709 return fdt_getprop(initial_boot_params, node, name, size);
710}
711
712/**
713 * of_fdt_is_compatible - Return true if given node from the given blob has
714 * compat in its compatible list
715 * @blob: A device tree blob
716 * @node: node to test
717 * @compat: compatible string to compare with compatible list.
718 *
719 * On match, returns a non-zero value with smaller values returned for more
720 * specific compatible values.
721 */
722static int of_fdt_is_compatible(const void *blob,
723 unsigned long node, const char *compat)
724{
725 const char *cp;
726 int cplen;
727 unsigned long l, score = 0;
728
729 cp = fdt_getprop(blob, node, "compatible", &cplen);
730 if (cp == NULL)
731 return 0;
732 while (cplen > 0) {
733 score++;
734 if (of_compat_cmp(cp, compat, strlen(compat)) == 0)
735 return score;
736 l = strlen(cp) + 1;
737 cp += l;
738 cplen -= l;
739 }
740
741 return 0;
742}
743
744/**
745 * of_flat_dt_is_compatible - Return true if given node has compat in compatible list
746 * @node: node to test
747 * @compat: compatible string to compare with compatible list.
748 */
749int __init of_flat_dt_is_compatible(unsigned long node, const char *compat)
750{
751 return of_fdt_is_compatible(initial_boot_params, node, compat);
752}
753
754/**
755 * of_flat_dt_match - Return true if node matches a list of compatible values
756 */
757static int __init of_flat_dt_match(unsigned long node, const char *const *compat)
758{
759 unsigned int tmp, score = 0;
760
761 if (!compat)
762 return 0;
763
764 while (*compat) {
765 tmp = of_fdt_is_compatible(initial_boot_params, node, *compat);
766 if (tmp && (score == 0 || (tmp < score)))
767 score = tmp;
768 compat++;
769 }
770
771 return score;
772}
773
774/**
775 * of_get_flat_dt_prop - Given a node in the flat blob, return the phandle
776 */
777uint32_t __init of_get_flat_dt_phandle(unsigned long node)
778{
779 return fdt_get_phandle(initial_boot_params, node);
780}
781
782struct fdt_scan_status {
783 const char *name;
784 int namelen;
785 int depth;
786 int found;
787 int (*iterator)(unsigned long node, const char *uname, int depth, void *data);
788 void *data;
789};
790
791const char * __init of_flat_dt_get_machine_name(void)
792{
793 const char *name;
794 unsigned long dt_root = of_get_flat_dt_root();
795
796 name = of_get_flat_dt_prop(dt_root, "model", NULL);
797 if (!name)
798 name = of_get_flat_dt_prop(dt_root, "compatible", NULL);
799 return name;
800}
801
802/**
803 * of_flat_dt_match_machine - Iterate match tables to find matching machine.
804 *
805 * @default_match: A machine specific ptr to return in case of no match.
806 * @get_next_compat: callback function to return next compatible match table.
807 *
808 * Iterate through machine match tables to find the best match for the machine
809 * compatible string in the FDT.
810 */
811const void * __init of_flat_dt_match_machine(const void *default_match,
812 const void * (*get_next_compat)(const char * const**))
813{
814 const void *data = NULL;
815 const void *best_data = default_match;
816 const char *const *compat;
817 unsigned long dt_root;
818 unsigned int best_score = ~1, score = 0;
819
820 dt_root = of_get_flat_dt_root();
821 while ((data = get_next_compat(&compat))) {
822 score = of_flat_dt_match(dt_root, compat);
823 if (score > 0 && score < best_score) {
824 best_data = data;
825 best_score = score;
826 }
827 }
828 if (!best_data) {
829 const char *prop;
830 int size;
831
832 pr_err("\n unrecognized device tree list:\n[ ");
833
834 prop = of_get_flat_dt_prop(dt_root, "compatible", &size);
835 if (prop) {
836 while (size > 0) {
837 printk("'%s' ", prop);
838 size -= strlen(prop) + 1;
839 prop += strlen(prop) + 1;
840 }
841 }
842 printk("]\n\n");
843 return NULL;
844 }
845
846 pr_info("Machine model: %s\n", of_flat_dt_get_machine_name());
847
848 return best_data;
849}
850
851#ifdef CONFIG_BLK_DEV_INITRD
852static void __early_init_dt_declare_initrd(unsigned long start,
853 unsigned long end)
854{
855 /* ARM64 would cause a BUG to occur here when CONFIG_DEBUG_VM is
856 * enabled since __va() is called too early. ARM64 does make use
857 * of phys_initrd_start/phys_initrd_size so we can skip this
858 * conversion.
859 */
860 if (!IS_ENABLED(CONFIG_ARM64)) {
861 initrd_start = (unsigned long)__va(start);
862 initrd_end = (unsigned long)__va(end);
863 initrd_below_start_ok = 1;
864 }
865}
866
867/**
868 * early_init_dt_check_for_initrd - Decode initrd location from flat tree
869 * @node: reference to node containing initrd location ('chosen')
870 */
871static void __init early_init_dt_check_for_initrd(unsigned long node)
872{
873 u64 start, end;
874 int len;
875 const __be32 *prop;
876
877 pr_debug("Looking for initrd properties... ");
878
879 prop = of_get_flat_dt_prop(node, "linux,initrd-start", &len);
880 if (!prop)
881 return;
882 start = of_read_number(prop, len/4);
883
884 prop = of_get_flat_dt_prop(node, "linux,initrd-end", &len);
885 if (!prop)
886 return;
887 end = of_read_number(prop, len/4);
888
889 __early_init_dt_declare_initrd(start, end);
890 phys_initrd_start = start;
891 phys_initrd_size = end - start;
892
893 pr_debug("initrd_start=0x%llx initrd_end=0x%llx\n",
894 (unsigned long long)start, (unsigned long long)end);
895}
896#else
897static inline void early_init_dt_check_for_initrd(unsigned long node)
898{
899}
900#endif /* CONFIG_BLK_DEV_INITRD */
901
902#ifdef CONFIG_SERIAL_EARLYCON
903
904int __init early_init_dt_scan_chosen_stdout(void)
905{
906 int offset;
907 const char *p, *q, *options = NULL;
908 int l;
909 const struct earlycon_id **p_match;
910 const void *fdt = initial_boot_params;
911
912 offset = fdt_path_offset(fdt, "/chosen");
913 if (offset < 0)
914 offset = fdt_path_offset(fdt, "/chosen@0");
915 if (offset < 0)
916 return -ENOENT;
917
918 p = fdt_getprop(fdt, offset, "stdout-path", &l);
919 if (!p)
920 p = fdt_getprop(fdt, offset, "linux,stdout-path", &l);
921 if (!p || !l)
922 return -ENOENT;
923
924 q = strchrnul(p, ':');
925 if (*q != '\0')
926 options = q + 1;
927 l = q - p;
928
929 /* Get the node specified by stdout-path */
930 offset = fdt_path_offset_namelen(fdt, p, l);
931 if (offset < 0) {
932 pr_warn("earlycon: stdout-path %.*s not found\n", l, p);
933 return 0;
934 }
935
936 for (p_match = __earlycon_table; p_match < __earlycon_table_end;
937 p_match++) {
938 const struct earlycon_id *match = *p_match;
939
940 if (!match->compatible[0])
941 continue;
942
943 if (fdt_node_check_compatible(fdt, offset, match->compatible))
944 continue;
945
946 if (of_setup_earlycon(match, offset, options) == 0)
947 return 0;
948 }
949 return -ENODEV;
950}
951#endif
952
953/**
954 * early_init_dt_scan_root - fetch the top level address and size cells
955 */
956int __init early_init_dt_scan_root(unsigned long node, const char *uname,
957 int depth, void *data)
958{
959 const __be32 *prop;
960
961 if (depth != 0)
962 return 0;
963
964 dt_root_size_cells = OF_ROOT_NODE_SIZE_CELLS_DEFAULT;
965 dt_root_addr_cells = OF_ROOT_NODE_ADDR_CELLS_DEFAULT;
966
967 prop = of_get_flat_dt_prop(node, "#size-cells", NULL);
968 if (prop)
969 dt_root_size_cells = be32_to_cpup(prop);
970 pr_debug("dt_root_size_cells = %x\n", dt_root_size_cells);
971
972 prop = of_get_flat_dt_prop(node, "#address-cells", NULL);
973 if (prop)
974 dt_root_addr_cells = be32_to_cpup(prop);
975 pr_debug("dt_root_addr_cells = %x\n", dt_root_addr_cells);
976
977 /* break now */
978 return 1;
979}
980
981u64 __init dt_mem_next_cell(int s, const __be32 **cellp)
982{
983 const __be32 *p = *cellp;
984
985 *cellp = p + s;
986 return of_read_number(p, s);
987}
988
989/**
990 * early_init_dt_scan_memory - Look for and parse memory nodes
991 */
992int __init early_init_dt_scan_memory(unsigned long node, const char *uname,
993 int depth, void *data)
994{
995 const char *type = of_get_flat_dt_prop(node, "device_type", NULL);
996 const __be32 *reg, *endp;
997 int l;
998 bool hotpluggable;
999
1000 /* We are scanning "memory" nodes only */
1001 if (type == NULL || strcmp(type, "memory") != 0)
1002 return 0;
1003
1004 reg = of_get_flat_dt_prop(node, "linux,usable-memory", &l);
1005 if (reg == NULL)
1006 reg = of_get_flat_dt_prop(node, "reg", &l);
1007 if (reg == NULL)
1008 return 0;
1009
1010 endp = reg + (l / sizeof(__be32));
1011 hotpluggable = of_get_flat_dt_prop(node, "hotpluggable", NULL);
1012
1013 pr_debug("memory scan node %s, reg size %d,\n", uname, l);
1014
1015 while ((endp - reg) >= (dt_root_addr_cells + dt_root_size_cells)) {
1016 u64 base, size;
1017
1018 base = dt_mem_next_cell(dt_root_addr_cells, ®);
1019 size = dt_mem_next_cell(dt_root_size_cells, ®);
1020
1021 if (size == 0)
1022 continue;
1023 pr_debug(" - %llx , %llx\n", (unsigned long long)base,
1024 (unsigned long long)size);
1025
1026 early_init_dt_add_memory_arch(base, size);
1027
1028 if (!hotpluggable)
1029 continue;
1030
1031 if (early_init_dt_mark_hotplug_memory_arch(base, size))
1032 pr_warn("failed to mark hotplug range 0x%llx - 0x%llx\n",
1033 base, base + size);
1034 }
1035
1036 return 0;
1037}
1038
1039int __init early_init_dt_scan_chosen(unsigned long node, const char *uname,
1040 int depth, void *data)
1041{
1042 int l;
1043 const char *p;
1044 const void *rng_seed;
1045
1046 pr_debug("search \"chosen\", depth: %d, uname: %s\n", depth, uname);
1047
1048 if (depth != 1 || !data ||
1049 (strcmp(uname, "chosen") != 0 && strcmp(uname, "chosen@0") != 0))
1050 return 0;
1051
1052 early_init_dt_check_for_initrd(node);
1053
1054 /* Retrieve command line */
1055 p = of_get_flat_dt_prop(node, "bootargs", &l);
1056 if (p != NULL && l > 0)
1057 strlcpy(data, p, min(l, COMMAND_LINE_SIZE));
1058
1059 /*
1060 * CONFIG_CMDLINE is meant to be a default in case nothing else
1061 * managed to set the command line, unless CONFIG_CMDLINE_FORCE
1062 * is set in which case we override whatever was found earlier.
1063 */
1064#ifdef CONFIG_CMDLINE
1065#if defined(CONFIG_CMDLINE_EXTEND)
1066 strlcat(data, " ", COMMAND_LINE_SIZE);
1067 strlcat(data, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
1068#elif defined(CONFIG_CMDLINE_FORCE)
1069 strlcpy(data, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
1070#else
1071 /* No arguments from boot loader, use kernel's cmdl*/
1072 if (!((char *)data)[0])
1073 strlcpy(data, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
1074#endif
1075#endif /* CONFIG_CMDLINE */
1076
1077 pr_debug("Command line is: %s\n", (char *)data);
1078
1079 rng_seed = of_get_flat_dt_prop(node, "rng-seed", &l);
1080 if (rng_seed && l > 0) {
1081 add_bootloader_randomness(rng_seed, l);
1082
1083 /* try to clear seed so it won't be found. */
1084 fdt_nop_property(initial_boot_params, node, "rng-seed");
1085
1086 /* update CRC check value */
1087 of_fdt_crc32 = crc32_be(~0, initial_boot_params,
1088 fdt_totalsize(initial_boot_params));
1089 }
1090
1091 /* break now */
1092 return 1;
1093}
1094
1095#ifndef MIN_MEMBLOCK_ADDR
1096#define MIN_MEMBLOCK_ADDR __pa(PAGE_OFFSET)
1097#endif
1098#ifndef MAX_MEMBLOCK_ADDR
1099#define MAX_MEMBLOCK_ADDR ((phys_addr_t)~0)
1100#endif
1101
1102void __init __weak early_init_dt_add_memory_arch(u64 base, u64 size)
1103{
1104 const u64 phys_offset = MIN_MEMBLOCK_ADDR;
1105
1106 if (size < PAGE_SIZE - (base & ~PAGE_MASK)) {
1107 pr_warn("Ignoring memory block 0x%llx - 0x%llx\n",
1108 base, base + size);
1109 return;
1110 }
1111
1112 if (!PAGE_ALIGNED(base)) {
1113 size -= PAGE_SIZE - (base & ~PAGE_MASK);
1114 base = PAGE_ALIGN(base);
1115 }
1116 size &= PAGE_MASK;
1117
1118 if (base > MAX_MEMBLOCK_ADDR) {
1119 pr_warn("Ignoring memory block 0x%llx - 0x%llx\n",
1120 base, base + size);
1121 return;
1122 }
1123
1124 if (base + size - 1 > MAX_MEMBLOCK_ADDR) {
1125 pr_warn("Ignoring memory range 0x%llx - 0x%llx\n",
1126 ((u64)MAX_MEMBLOCK_ADDR) + 1, base + size);
1127 size = MAX_MEMBLOCK_ADDR - base + 1;
1128 }
1129
1130 if (base + size < phys_offset) {
1131 pr_warn("Ignoring memory block 0x%llx - 0x%llx\n",
1132 base, base + size);
1133 return;
1134 }
1135 if (base < phys_offset) {
1136 pr_warn("Ignoring memory range 0x%llx - 0x%llx\n",
1137 base, phys_offset);
1138 size -= phys_offset - base;
1139 base = phys_offset;
1140 }
1141 memblock_add(base, size);
1142}
1143
1144int __init __weak early_init_dt_mark_hotplug_memory_arch(u64 base, u64 size)
1145{
1146 return memblock_mark_hotplug(base, size);
1147}
1148
1149int __init __weak early_init_dt_reserve_memory_arch(phys_addr_t base,
1150 phys_addr_t size, bool nomap)
1151{
1152 if (nomap)
1153 return memblock_remove(base, size);
1154 return memblock_reserve(base, size);
1155}
1156
1157static void * __init early_init_dt_alloc_memory_arch(u64 size, u64 align)
1158{
1159 void *ptr = memblock_alloc(size, align);
1160
1161 if (!ptr)
1162 panic("%s: Failed to allocate %llu bytes align=0x%llx\n",
1163 __func__, size, align);
1164
1165 return ptr;
1166}
1167
1168bool __init early_init_dt_verify(void *params)
1169{
1170 if (!params)
1171 return false;
1172
1173 /* check device tree validity */
1174 if (fdt_check_header(params))
1175 return false;
1176
1177 /* Setup flat device-tree pointer */
1178 initial_boot_params = params;
1179 of_fdt_crc32 = crc32_be(~0, initial_boot_params,
1180 fdt_totalsize(initial_boot_params));
1181 return true;
1182}
1183
1184
1185void __init early_init_dt_scan_nodes(void)
1186{
1187 int rc = 0;
1188
1189 /* Retrieve various information from the /chosen node */
1190 rc = of_scan_flat_dt(early_init_dt_scan_chosen, boot_command_line);
1191 if (!rc)
1192 pr_warn("No chosen node found, continuing without\n");
1193
1194 /* Initialize {size,address}-cells info */
1195 of_scan_flat_dt(early_init_dt_scan_root, NULL);
1196
1197 /* Setup memory, calling early_init_dt_add_memory_arch */
1198 of_scan_flat_dt(early_init_dt_scan_memory, NULL);
1199}
1200
1201bool __init early_init_dt_scan(void *params)
1202{
1203 bool status;
1204
1205 status = early_init_dt_verify(params);
1206 if (!status)
1207 return false;
1208
1209 early_init_dt_scan_nodes();
1210 return true;
1211}
1212
1213/**
1214 * unflatten_device_tree - create tree of device_nodes from flat blob
1215 *
1216 * unflattens the device-tree passed by the firmware, creating the
1217 * tree of struct device_node. It also fills the "name" and "type"
1218 * pointers of the nodes so the normal device-tree walking functions
1219 * can be used.
1220 */
1221void __init unflatten_device_tree(void)
1222{
1223 __unflatten_device_tree(initial_boot_params, NULL, &of_root,
1224 early_init_dt_alloc_memory_arch, false);
1225
1226 /* Get pointer to "/chosen" and "/aliases" nodes for use everywhere */
1227 of_alias_scan(early_init_dt_alloc_memory_arch);
1228
1229 unittest_unflatten_overlay_base();
1230}
1231
1232/**
1233 * unflatten_and_copy_device_tree - copy and create tree of device_nodes from flat blob
1234 *
1235 * Copies and unflattens the device-tree passed by the firmware, creating the
1236 * tree of struct device_node. It also fills the "name" and "type"
1237 * pointers of the nodes so the normal device-tree walking functions
1238 * can be used. This should only be used when the FDT memory has not been
1239 * reserved such is the case when the FDT is built-in to the kernel init
1240 * section. If the FDT memory is reserved already then unflatten_device_tree
1241 * should be used instead.
1242 */
1243void __init unflatten_and_copy_device_tree(void)
1244{
1245 int size;
1246 void *dt;
1247
1248 if (!initial_boot_params) {
1249 pr_warn("No valid device tree found, continuing without\n");
1250 return;
1251 }
1252
1253 size = fdt_totalsize(initial_boot_params);
1254 dt = early_init_dt_alloc_memory_arch(size,
1255 roundup_pow_of_two(FDT_V17_SIZE));
1256
1257 if (dt) {
1258 memcpy(dt, initial_boot_params, size);
1259 initial_boot_params = dt;
1260 }
1261 unflatten_device_tree();
1262}
1263
1264#ifdef CONFIG_SYSFS
1265static ssize_t of_fdt_raw_read(struct file *filp, struct kobject *kobj,
1266 struct bin_attribute *bin_attr,
1267 char *buf, loff_t off, size_t count)
1268{
1269 memcpy(buf, initial_boot_params + off, count);
1270 return count;
1271}
1272
1273static int __init of_fdt_raw_init(void)
1274{
1275 static struct bin_attribute of_fdt_raw_attr =
1276 __BIN_ATTR(fdt, S_IRUSR, of_fdt_raw_read, NULL, 0);
1277
1278 if (!initial_boot_params)
1279 return 0;
1280
1281 if (of_fdt_crc32 != crc32_be(~0, initial_boot_params,
1282 fdt_totalsize(initial_boot_params))) {
1283 pr_warn("not creating '/sys/firmware/fdt': CRC check failed\n");
1284 return 0;
1285 }
1286 of_fdt_raw_attr.size = fdt_totalsize(initial_boot_params);
1287 return sysfs_create_bin_file(firmware_kobj, &of_fdt_raw_attr);
1288}
1289late_initcall(of_fdt_raw_init);
1290#endif
1291
1292#endif /* CONFIG_OF_EARLY_FLATTREE */
1/*
2 * Functions for working with the Flattened Device Tree data format
3 *
4 * Copyright 2009 Benjamin Herrenschmidt, IBM Corp
5 * benh@kernel.crashing.org
6 *
7 * This program is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License
9 * version 2 as published by the Free Software Foundation.
10 */
11
12#include <linux/kernel.h>
13#include <linux/initrd.h>
14#include <linux/module.h>
15#include <linux/of.h>
16#include <linux/of_fdt.h>
17#include <linux/string.h>
18#include <linux/errno.h>
19#include <linux/slab.h>
20
21#ifdef CONFIG_PPC
22#include <asm/machdep.h>
23#endif /* CONFIG_PPC */
24
25#include <asm/page.h>
26
27char *of_fdt_get_string(struct boot_param_header *blob, u32 offset)
28{
29 return ((char *)blob) +
30 be32_to_cpu(blob->off_dt_strings) + offset;
31}
32
33/**
34 * of_fdt_get_property - Given a node in the given flat blob, return
35 * the property ptr
36 */
37void *of_fdt_get_property(struct boot_param_header *blob,
38 unsigned long node, const char *name,
39 unsigned long *size)
40{
41 unsigned long p = node;
42
43 do {
44 u32 tag = be32_to_cpup((__be32 *)p);
45 u32 sz, noff;
46 const char *nstr;
47
48 p += 4;
49 if (tag == OF_DT_NOP)
50 continue;
51 if (tag != OF_DT_PROP)
52 return NULL;
53
54 sz = be32_to_cpup((__be32 *)p);
55 noff = be32_to_cpup((__be32 *)(p + 4));
56 p += 8;
57 if (be32_to_cpu(blob->version) < 0x10)
58 p = ALIGN(p, sz >= 8 ? 8 : 4);
59
60 nstr = of_fdt_get_string(blob, noff);
61 if (nstr == NULL) {
62 pr_warning("Can't find property index name !\n");
63 return NULL;
64 }
65 if (strcmp(name, nstr) == 0) {
66 if (size)
67 *size = sz;
68 return (void *)p;
69 }
70 p += sz;
71 p = ALIGN(p, 4);
72 } while (1);
73}
74
75/**
76 * of_fdt_is_compatible - Return true if given node from the given blob has
77 * compat in its compatible list
78 * @blob: A device tree blob
79 * @node: node to test
80 * @compat: compatible string to compare with compatible list.
81 *
82 * On match, returns a non-zero value with smaller values returned for more
83 * specific compatible values.
84 */
85int of_fdt_is_compatible(struct boot_param_header *blob,
86 unsigned long node, const char *compat)
87{
88 const char *cp;
89 unsigned long cplen, l, score = 0;
90
91 cp = of_fdt_get_property(blob, node, "compatible", &cplen);
92 if (cp == NULL)
93 return 0;
94 while (cplen > 0) {
95 score++;
96 if (of_compat_cmp(cp, compat, strlen(compat)) == 0)
97 return score;
98 l = strlen(cp) + 1;
99 cp += l;
100 cplen -= l;
101 }
102
103 return 0;
104}
105
106/**
107 * of_fdt_match - Return true if node matches a list of compatible values
108 */
109int of_fdt_match(struct boot_param_header *blob, unsigned long node,
110 const char **compat)
111{
112 unsigned int tmp, score = 0;
113
114 if (!compat)
115 return 0;
116
117 while (*compat) {
118 tmp = of_fdt_is_compatible(blob, node, *compat);
119 if (tmp && (score == 0 || (tmp < score)))
120 score = tmp;
121 compat++;
122 }
123
124 return score;
125}
126
127static void *unflatten_dt_alloc(unsigned long *mem, unsigned long size,
128 unsigned long align)
129{
130 void *res;
131
132 *mem = ALIGN(*mem, align);
133 res = (void *)*mem;
134 *mem += size;
135
136 return res;
137}
138
139/**
140 * unflatten_dt_node - Alloc and populate a device_node from the flat tree
141 * @blob: The parent device tree blob
142 * @mem: Memory chunk to use for allocating device nodes and properties
143 * @p: pointer to node in flat tree
144 * @dad: Parent struct device_node
145 * @allnextpp: pointer to ->allnext from last allocated device_node
146 * @fpsize: Size of the node path up at the current depth.
147 */
148static unsigned long unflatten_dt_node(struct boot_param_header *blob,
149 unsigned long mem,
150 unsigned long *p,
151 struct device_node *dad,
152 struct device_node ***allnextpp,
153 unsigned long fpsize)
154{
155 struct device_node *np;
156 struct property *pp, **prev_pp = NULL;
157 char *pathp;
158 u32 tag;
159 unsigned int l, allocl;
160 int has_name = 0;
161 int new_format = 0;
162
163 tag = be32_to_cpup((__be32 *)(*p));
164 if (tag != OF_DT_BEGIN_NODE) {
165 pr_err("Weird tag at start of node: %x\n", tag);
166 return mem;
167 }
168 *p += 4;
169 pathp = (char *)*p;
170 l = allocl = strlen(pathp) + 1;
171 *p = ALIGN(*p + l, 4);
172
173 /* version 0x10 has a more compact unit name here instead of the full
174 * path. we accumulate the full path size using "fpsize", we'll rebuild
175 * it later. We detect this because the first character of the name is
176 * not '/'.
177 */
178 if ((*pathp) != '/') {
179 new_format = 1;
180 if (fpsize == 0) {
181 /* root node: special case. fpsize accounts for path
182 * plus terminating zero. root node only has '/', so
183 * fpsize should be 2, but we want to avoid the first
184 * level nodes to have two '/' so we use fpsize 1 here
185 */
186 fpsize = 1;
187 allocl = 2;
188 } else {
189 /* account for '/' and path size minus terminal 0
190 * already in 'l'
191 */
192 fpsize += l;
193 allocl = fpsize;
194 }
195 }
196
197 np = unflatten_dt_alloc(&mem, sizeof(struct device_node) + allocl,
198 __alignof__(struct device_node));
199 if (allnextpp) {
200 memset(np, 0, sizeof(*np));
201 np->full_name = ((char *)np) + sizeof(struct device_node);
202 if (new_format) {
203 char *fn = np->full_name;
204 /* rebuild full path for new format */
205 if (dad && dad->parent) {
206 strcpy(fn, dad->full_name);
207#ifdef DEBUG
208 if ((strlen(fn) + l + 1) != allocl) {
209 pr_debug("%s: p: %d, l: %d, a: %d\n",
210 pathp, (int)strlen(fn),
211 l, allocl);
212 }
213#endif
214 fn += strlen(fn);
215 }
216 *(fn++) = '/';
217 memcpy(fn, pathp, l);
218 } else
219 memcpy(np->full_name, pathp, l);
220 prev_pp = &np->properties;
221 **allnextpp = np;
222 *allnextpp = &np->allnext;
223 if (dad != NULL) {
224 np->parent = dad;
225 /* we temporarily use the next field as `last_child'*/
226 if (dad->next == NULL)
227 dad->child = np;
228 else
229 dad->next->sibling = np;
230 dad->next = np;
231 }
232 kref_init(&np->kref);
233 }
234 /* process properties */
235 while (1) {
236 u32 sz, noff;
237 char *pname;
238
239 tag = be32_to_cpup((__be32 *)(*p));
240 if (tag == OF_DT_NOP) {
241 *p += 4;
242 continue;
243 }
244 if (tag != OF_DT_PROP)
245 break;
246 *p += 4;
247 sz = be32_to_cpup((__be32 *)(*p));
248 noff = be32_to_cpup((__be32 *)((*p) + 4));
249 *p += 8;
250 if (be32_to_cpu(blob->version) < 0x10)
251 *p = ALIGN(*p, sz >= 8 ? 8 : 4);
252
253 pname = of_fdt_get_string(blob, noff);
254 if (pname == NULL) {
255 pr_info("Can't find property name in list !\n");
256 break;
257 }
258 if (strcmp(pname, "name") == 0)
259 has_name = 1;
260 l = strlen(pname) + 1;
261 pp = unflatten_dt_alloc(&mem, sizeof(struct property),
262 __alignof__(struct property));
263 if (allnextpp) {
264 /* We accept flattened tree phandles either in
265 * ePAPR-style "phandle" properties, or the
266 * legacy "linux,phandle" properties. If both
267 * appear and have different values, things
268 * will get weird. Don't do that. */
269 if ((strcmp(pname, "phandle") == 0) ||
270 (strcmp(pname, "linux,phandle") == 0)) {
271 if (np->phandle == 0)
272 np->phandle = be32_to_cpup((__be32*)*p);
273 }
274 /* And we process the "ibm,phandle" property
275 * used in pSeries dynamic device tree
276 * stuff */
277 if (strcmp(pname, "ibm,phandle") == 0)
278 np->phandle = be32_to_cpup((__be32 *)*p);
279 pp->name = pname;
280 pp->length = sz;
281 pp->value = (void *)*p;
282 *prev_pp = pp;
283 prev_pp = &pp->next;
284 }
285 *p = ALIGN((*p) + sz, 4);
286 }
287 /* with version 0x10 we may not have the name property, recreate
288 * it here from the unit name if absent
289 */
290 if (!has_name) {
291 char *p1 = pathp, *ps = pathp, *pa = NULL;
292 int sz;
293
294 while (*p1) {
295 if ((*p1) == '@')
296 pa = p1;
297 if ((*p1) == '/')
298 ps = p1 + 1;
299 p1++;
300 }
301 if (pa < ps)
302 pa = p1;
303 sz = (pa - ps) + 1;
304 pp = unflatten_dt_alloc(&mem, sizeof(struct property) + sz,
305 __alignof__(struct property));
306 if (allnextpp) {
307 pp->name = "name";
308 pp->length = sz;
309 pp->value = pp + 1;
310 *prev_pp = pp;
311 prev_pp = &pp->next;
312 memcpy(pp->value, ps, sz - 1);
313 ((char *)pp->value)[sz - 1] = 0;
314 pr_debug("fixed up name for %s -> %s\n", pathp,
315 (char *)pp->value);
316 }
317 }
318 if (allnextpp) {
319 *prev_pp = NULL;
320 np->name = of_get_property(np, "name", NULL);
321 np->type = of_get_property(np, "device_type", NULL);
322
323 if (!np->name)
324 np->name = "<NULL>";
325 if (!np->type)
326 np->type = "<NULL>";
327 }
328 while (tag == OF_DT_BEGIN_NODE || tag == OF_DT_NOP) {
329 if (tag == OF_DT_NOP)
330 *p += 4;
331 else
332 mem = unflatten_dt_node(blob, mem, p, np, allnextpp,
333 fpsize);
334 tag = be32_to_cpup((__be32 *)(*p));
335 }
336 if (tag != OF_DT_END_NODE) {
337 pr_err("Weird tag at end of node: %x\n", tag);
338 return mem;
339 }
340 *p += 4;
341 return mem;
342}
343
344/**
345 * __unflatten_device_tree - create tree of device_nodes from flat blob
346 *
347 * unflattens a device-tree, creating the
348 * tree of struct device_node. It also fills the "name" and "type"
349 * pointers of the nodes so the normal device-tree walking functions
350 * can be used.
351 * @blob: The blob to expand
352 * @mynodes: The device_node tree created by the call
353 * @dt_alloc: An allocator that provides a virtual address to memory
354 * for the resulting tree
355 */
356static void __unflatten_device_tree(struct boot_param_header *blob,
357 struct device_node **mynodes,
358 void * (*dt_alloc)(u64 size, u64 align))
359{
360 unsigned long start, mem, size;
361 struct device_node **allnextp = mynodes;
362
363 pr_debug(" -> unflatten_device_tree()\n");
364
365 if (!blob) {
366 pr_debug("No device tree pointer\n");
367 return;
368 }
369
370 pr_debug("Unflattening device tree:\n");
371 pr_debug("magic: %08x\n", be32_to_cpu(blob->magic));
372 pr_debug("size: %08x\n", be32_to_cpu(blob->totalsize));
373 pr_debug("version: %08x\n", be32_to_cpu(blob->version));
374
375 if (be32_to_cpu(blob->magic) != OF_DT_HEADER) {
376 pr_err("Invalid device tree blob header\n");
377 return;
378 }
379
380 /* First pass, scan for size */
381 start = ((unsigned long)blob) +
382 be32_to_cpu(blob->off_dt_struct);
383 size = unflatten_dt_node(blob, 0, &start, NULL, NULL, 0);
384 size = (size | 3) + 1;
385
386 pr_debug(" size is %lx, allocating...\n", size);
387
388 /* Allocate memory for the expanded device tree */
389 mem = (unsigned long)
390 dt_alloc(size + 4, __alignof__(struct device_node));
391
392 ((__be32 *)mem)[size / 4] = cpu_to_be32(0xdeadbeef);
393
394 pr_debug(" unflattening %lx...\n", mem);
395
396 /* Second pass, do actual unflattening */
397 start = ((unsigned long)blob) +
398 be32_to_cpu(blob->off_dt_struct);
399 unflatten_dt_node(blob, mem, &start, NULL, &allnextp, 0);
400 if (be32_to_cpup((__be32 *)start) != OF_DT_END)
401 pr_warning("Weird tag at end of tree: %08x\n", *((u32 *)start));
402 if (be32_to_cpu(((__be32 *)mem)[size / 4]) != 0xdeadbeef)
403 pr_warning("End of tree marker overwritten: %08x\n",
404 be32_to_cpu(((__be32 *)mem)[size / 4]));
405 *allnextp = NULL;
406
407 pr_debug(" <- unflatten_device_tree()\n");
408}
409
410static void *kernel_tree_alloc(u64 size, u64 align)
411{
412 return kzalloc(size, GFP_KERNEL);
413}
414
415/**
416 * of_fdt_unflatten_tree - create tree of device_nodes from flat blob
417 *
418 * unflattens the device-tree passed by the firmware, creating the
419 * tree of struct device_node. It also fills the "name" and "type"
420 * pointers of the nodes so the normal device-tree walking functions
421 * can be used.
422 */
423void of_fdt_unflatten_tree(unsigned long *blob,
424 struct device_node **mynodes)
425{
426 struct boot_param_header *device_tree =
427 (struct boot_param_header *)blob;
428 __unflatten_device_tree(device_tree, mynodes, &kernel_tree_alloc);
429}
430EXPORT_SYMBOL_GPL(of_fdt_unflatten_tree);
431
432/* Everything below here references initial_boot_params directly. */
433int __initdata dt_root_addr_cells;
434int __initdata dt_root_size_cells;
435
436struct boot_param_header *initial_boot_params;
437
438#ifdef CONFIG_OF_EARLY_FLATTREE
439
440/**
441 * of_scan_flat_dt - scan flattened tree blob and call callback on each.
442 * @it: callback function
443 * @data: context data pointer
444 *
445 * This function is used to scan the flattened device-tree, it is
446 * used to extract the memory information at boot before we can
447 * unflatten the tree
448 */
449int __init of_scan_flat_dt(int (*it)(unsigned long node,
450 const char *uname, int depth,
451 void *data),
452 void *data)
453{
454 unsigned long p = ((unsigned long)initial_boot_params) +
455 be32_to_cpu(initial_boot_params->off_dt_struct);
456 int rc = 0;
457 int depth = -1;
458
459 do {
460 u32 tag = be32_to_cpup((__be32 *)p);
461 char *pathp;
462
463 p += 4;
464 if (tag == OF_DT_END_NODE) {
465 depth--;
466 continue;
467 }
468 if (tag == OF_DT_NOP)
469 continue;
470 if (tag == OF_DT_END)
471 break;
472 if (tag == OF_DT_PROP) {
473 u32 sz = be32_to_cpup((__be32 *)p);
474 p += 8;
475 if (be32_to_cpu(initial_boot_params->version) < 0x10)
476 p = ALIGN(p, sz >= 8 ? 8 : 4);
477 p += sz;
478 p = ALIGN(p, 4);
479 continue;
480 }
481 if (tag != OF_DT_BEGIN_NODE) {
482 pr_err("Invalid tag %x in flat device tree!\n", tag);
483 return -EINVAL;
484 }
485 depth++;
486 pathp = (char *)p;
487 p = ALIGN(p + strlen(pathp) + 1, 4);
488 if ((*pathp) == '/') {
489 char *lp, *np;
490 for (lp = NULL, np = pathp; *np; np++)
491 if ((*np) == '/')
492 lp = np+1;
493 if (lp != NULL)
494 pathp = lp;
495 }
496 rc = it(p, pathp, depth, data);
497 if (rc != 0)
498 break;
499 } while (1);
500
501 return rc;
502}
503
504/**
505 * of_get_flat_dt_root - find the root node in the flat blob
506 */
507unsigned long __init of_get_flat_dt_root(void)
508{
509 unsigned long p = ((unsigned long)initial_boot_params) +
510 be32_to_cpu(initial_boot_params->off_dt_struct);
511
512 while (be32_to_cpup((__be32 *)p) == OF_DT_NOP)
513 p += 4;
514 BUG_ON(be32_to_cpup((__be32 *)p) != OF_DT_BEGIN_NODE);
515 p += 4;
516 return ALIGN(p + strlen((char *)p) + 1, 4);
517}
518
519/**
520 * of_get_flat_dt_prop - Given a node in the flat blob, return the property ptr
521 *
522 * This function can be used within scan_flattened_dt callback to get
523 * access to properties
524 */
525void *__init of_get_flat_dt_prop(unsigned long node, const char *name,
526 unsigned long *size)
527{
528 return of_fdt_get_property(initial_boot_params, node, name, size);
529}
530
531/**
532 * of_flat_dt_is_compatible - Return true if given node has compat in compatible list
533 * @node: node to test
534 * @compat: compatible string to compare with compatible list.
535 */
536int __init of_flat_dt_is_compatible(unsigned long node, const char *compat)
537{
538 return of_fdt_is_compatible(initial_boot_params, node, compat);
539}
540
541/**
542 * of_flat_dt_match - Return true if node matches a list of compatible values
543 */
544int __init of_flat_dt_match(unsigned long node, const char **compat)
545{
546 return of_fdt_match(initial_boot_params, node, compat);
547}
548
549#ifdef CONFIG_BLK_DEV_INITRD
550/**
551 * early_init_dt_check_for_initrd - Decode initrd location from flat tree
552 * @node: reference to node containing initrd location ('chosen')
553 */
554void __init early_init_dt_check_for_initrd(unsigned long node)
555{
556 unsigned long start, end, len;
557 __be32 *prop;
558
559 pr_debug("Looking for initrd properties... ");
560
561 prop = of_get_flat_dt_prop(node, "linux,initrd-start", &len);
562 if (!prop)
563 return;
564 start = of_read_ulong(prop, len/4);
565
566 prop = of_get_flat_dt_prop(node, "linux,initrd-end", &len);
567 if (!prop)
568 return;
569 end = of_read_ulong(prop, len/4);
570
571 early_init_dt_setup_initrd_arch(start, end);
572 pr_debug("initrd_start=0x%lx initrd_end=0x%lx\n", start, end);
573}
574#else
575inline void early_init_dt_check_for_initrd(unsigned long node)
576{
577}
578#endif /* CONFIG_BLK_DEV_INITRD */
579
580/**
581 * early_init_dt_scan_root - fetch the top level address and size cells
582 */
583int __init early_init_dt_scan_root(unsigned long node, const char *uname,
584 int depth, void *data)
585{
586 __be32 *prop;
587
588 if (depth != 0)
589 return 0;
590
591 dt_root_size_cells = OF_ROOT_NODE_SIZE_CELLS_DEFAULT;
592 dt_root_addr_cells = OF_ROOT_NODE_ADDR_CELLS_DEFAULT;
593
594 prop = of_get_flat_dt_prop(node, "#size-cells", NULL);
595 if (prop)
596 dt_root_size_cells = be32_to_cpup(prop);
597 pr_debug("dt_root_size_cells = %x\n", dt_root_size_cells);
598
599 prop = of_get_flat_dt_prop(node, "#address-cells", NULL);
600 if (prop)
601 dt_root_addr_cells = be32_to_cpup(prop);
602 pr_debug("dt_root_addr_cells = %x\n", dt_root_addr_cells);
603
604 /* break now */
605 return 1;
606}
607
608u64 __init dt_mem_next_cell(int s, __be32 **cellp)
609{
610 __be32 *p = *cellp;
611
612 *cellp = p + s;
613 return of_read_number(p, s);
614}
615
616/**
617 * early_init_dt_scan_memory - Look for an parse memory nodes
618 */
619int __init early_init_dt_scan_memory(unsigned long node, const char *uname,
620 int depth, void *data)
621{
622 char *type = of_get_flat_dt_prop(node, "device_type", NULL);
623 __be32 *reg, *endp;
624 unsigned long l;
625
626 /* We are scanning "memory" nodes only */
627 if (type == NULL) {
628 /*
629 * The longtrail doesn't have a device_type on the
630 * /memory node, so look for the node called /memory@0.
631 */
632 if (depth != 1 || strcmp(uname, "memory@0") != 0)
633 return 0;
634 } else if (strcmp(type, "memory") != 0)
635 return 0;
636
637 reg = of_get_flat_dt_prop(node, "linux,usable-memory", &l);
638 if (reg == NULL)
639 reg = of_get_flat_dt_prop(node, "reg", &l);
640 if (reg == NULL)
641 return 0;
642
643 endp = reg + (l / sizeof(__be32));
644
645 pr_debug("memory scan node %s, reg size %ld, data: %x %x %x %x,\n",
646 uname, l, reg[0], reg[1], reg[2], reg[3]);
647
648 while ((endp - reg) >= (dt_root_addr_cells + dt_root_size_cells)) {
649 u64 base, size;
650
651 base = dt_mem_next_cell(dt_root_addr_cells, ®);
652 size = dt_mem_next_cell(dt_root_size_cells, ®);
653
654 if (size == 0)
655 continue;
656 pr_debug(" - %llx , %llx\n", (unsigned long long)base,
657 (unsigned long long)size);
658
659 early_init_dt_add_memory_arch(base, size);
660 }
661
662 return 0;
663}
664
665int __init early_init_dt_scan_chosen(unsigned long node, const char *uname,
666 int depth, void *data)
667{
668 unsigned long l;
669 char *p;
670
671 pr_debug("search \"chosen\", depth: %d, uname: %s\n", depth, uname);
672
673 if (depth != 1 || !data ||
674 (strcmp(uname, "chosen") != 0 && strcmp(uname, "chosen@0") != 0))
675 return 0;
676
677 early_init_dt_check_for_initrd(node);
678
679 /* Retrieve command line */
680 p = of_get_flat_dt_prop(node, "bootargs", &l);
681 if (p != NULL && l > 0)
682 strlcpy(data, p, min((int)l, COMMAND_LINE_SIZE));
683
684#ifdef CONFIG_CMDLINE
685#ifndef CONFIG_CMDLINE_FORCE
686 if (p == NULL || l == 0 || (l == 1 && (*p) == 0))
687#endif
688 strlcpy(data, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
689#endif /* CONFIG_CMDLINE */
690
691 pr_debug("Command line is: %s\n", (char*)data);
692
693 /* break now */
694 return 1;
695}
696
697/**
698 * unflatten_device_tree - create tree of device_nodes from flat blob
699 *
700 * unflattens the device-tree passed by the firmware, creating the
701 * tree of struct device_node. It also fills the "name" and "type"
702 * pointers of the nodes so the normal device-tree walking functions
703 * can be used.
704 */
705void __init unflatten_device_tree(void)
706{
707 __unflatten_device_tree(initial_boot_params, &allnodes,
708 early_init_dt_alloc_memory_arch);
709
710 /* Get pointer to OF "/chosen" node for use everywhere */
711 of_chosen = of_find_node_by_path("/chosen");
712 if (of_chosen == NULL)
713 of_chosen = of_find_node_by_path("/chosen@0");
714}
715
716#endif /* CONFIG_OF_EARLY_FLATTREE */