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1/*
2 * Functions for working with the Flattened Device Tree data format
3 *
4 * Copyright 2009 Benjamin Herrenschmidt, IBM Corp
5 * benh@kernel.crashing.org
6 *
7 * This program is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License
9 * version 2 as published by the Free Software Foundation.
10 */
11
12#include <linux/kernel.h>
13#include <linux/initrd.h>
14#include <linux/module.h>
15#include <linux/of.h>
16#include <linux/of_fdt.h>
17#include <linux/string.h>
18#include <linux/errno.h>
19#include <linux/slab.h>
20
21#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 */
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Functions for working with the Flattened Device Tree data format
4 *
5 * Copyright 2009 Benjamin Herrenschmidt, IBM Corp
6 * benh@kernel.crashing.org
7 */
8
9#define pr_fmt(fmt) "OF: fdt: " fmt
10
11#include <linux/crc32.h>
12#include <linux/kernel.h>
13#include <linux/initrd.h>
14#include <linux/memblock.h>
15#include <linux/mutex.h>
16#include <linux/of.h>
17#include <linux/of_fdt.h>
18#include <linux/of_reserved_mem.h>
19#include <linux/sizes.h>
20#include <linux/string.h>
21#include <linux/errno.h>
22#include <linux/slab.h>
23#include <linux/libfdt.h>
24#include <linux/debugfs.h>
25#include <linux/serial_core.h>
26#include <linux/sysfs.h>
27#include <linux/random.h>
28
29#include <asm/setup.h> /* for COMMAND_LINE_SIZE */
30#include <asm/page.h>
31
32#include "of_private.h"
33
34/*
35 * of_fdt_limit_memory - limit the number of regions in the /memory node
36 * @limit: maximum entries
37 *
38 * Adjust the flattened device tree to have at most 'limit' number of
39 * memory entries in the /memory node. This function may be called
40 * any time after initial_boot_param is set.
41 */
42void __init of_fdt_limit_memory(int limit)
43{
44 int memory;
45 int len;
46 const void *val;
47 int nr_address_cells = OF_ROOT_NODE_ADDR_CELLS_DEFAULT;
48 int nr_size_cells = OF_ROOT_NODE_SIZE_CELLS_DEFAULT;
49 const __be32 *addr_prop;
50 const __be32 *size_prop;
51 int root_offset;
52 int cell_size;
53
54 root_offset = fdt_path_offset(initial_boot_params, "/");
55 if (root_offset < 0)
56 return;
57
58 addr_prop = fdt_getprop(initial_boot_params, root_offset,
59 "#address-cells", NULL);
60 if (addr_prop)
61 nr_address_cells = fdt32_to_cpu(*addr_prop);
62
63 size_prop = fdt_getprop(initial_boot_params, root_offset,
64 "#size-cells", NULL);
65 if (size_prop)
66 nr_size_cells = fdt32_to_cpu(*size_prop);
67
68 cell_size = sizeof(uint32_t)*(nr_address_cells + nr_size_cells);
69
70 memory = fdt_path_offset(initial_boot_params, "/memory");
71 if (memory > 0) {
72 val = fdt_getprop(initial_boot_params, memory, "reg", &len);
73 if (len > limit*cell_size) {
74 len = limit*cell_size;
75 pr_debug("Limiting number of entries to %d\n", limit);
76 fdt_setprop(initial_boot_params, memory, "reg", val,
77 len);
78 }
79 }
80}
81
82static bool of_fdt_device_is_available(const void *blob, unsigned long node)
83{
84 const char *status = fdt_getprop(blob, node, "status", NULL);
85
86 if (!status)
87 return true;
88
89 if (!strcmp(status, "ok") || !strcmp(status, "okay"))
90 return true;
91
92 return false;
93}
94
95static void *unflatten_dt_alloc(void **mem, unsigned long size,
96 unsigned long align)
97{
98 void *res;
99
100 *mem = PTR_ALIGN(*mem, align);
101 res = *mem;
102 *mem += size;
103
104 return res;
105}
106
107static void populate_properties(const void *blob,
108 int offset,
109 void **mem,
110 struct device_node *np,
111 const char *nodename,
112 bool dryrun)
113{
114 struct property *pp, **pprev = NULL;
115 int cur;
116 bool has_name = false;
117
118 pprev = &np->properties;
119 for (cur = fdt_first_property_offset(blob, offset);
120 cur >= 0;
121 cur = fdt_next_property_offset(blob, cur)) {
122 const __be32 *val;
123 const char *pname;
124 u32 sz;
125
126 val = fdt_getprop_by_offset(blob, cur, &pname, &sz);
127 if (!val) {
128 pr_warn("Cannot locate property at 0x%x\n", cur);
129 continue;
130 }
131
132 if (!pname) {
133 pr_warn("Cannot find property name at 0x%x\n", cur);
134 continue;
135 }
136
137 if (!strcmp(pname, "name"))
138 has_name = true;
139
140 pp = unflatten_dt_alloc(mem, sizeof(struct property),
141 __alignof__(struct property));
142 if (dryrun)
143 continue;
144
145 /* We accept flattened tree phandles either in
146 * ePAPR-style "phandle" properties, or the
147 * legacy "linux,phandle" properties. If both
148 * appear and have different values, things
149 * will get weird. Don't do that.
150 */
151 if (!strcmp(pname, "phandle") ||
152 !strcmp(pname, "linux,phandle")) {
153 if (!np->phandle)
154 np->phandle = be32_to_cpup(val);
155 }
156
157 /* And we process the "ibm,phandle" property
158 * used in pSeries dynamic device tree
159 * stuff
160 */
161 if (!strcmp(pname, "ibm,phandle"))
162 np->phandle = be32_to_cpup(val);
163
164 pp->name = (char *)pname;
165 pp->length = sz;
166 pp->value = (__be32 *)val;
167 *pprev = pp;
168 pprev = &pp->next;
169 }
170
171 /* With version 0x10 we may not have the name property,
172 * recreate it here from the unit name if absent
173 */
174 if (!has_name) {
175 const char *p = nodename, *ps = p, *pa = NULL;
176 int len;
177
178 while (*p) {
179 if ((*p) == '@')
180 pa = p;
181 else if ((*p) == '/')
182 ps = p + 1;
183 p++;
184 }
185
186 if (pa < ps)
187 pa = p;
188 len = (pa - ps) + 1;
189 pp = unflatten_dt_alloc(mem, sizeof(struct property) + len,
190 __alignof__(struct property));
191 if (!dryrun) {
192 pp->name = "name";
193 pp->length = len;
194 pp->value = pp + 1;
195 *pprev = pp;
196 pprev = &pp->next;
197 memcpy(pp->value, ps, len - 1);
198 ((char *)pp->value)[len - 1] = 0;
199 pr_debug("fixed up name for %s -> %s\n",
200 nodename, (char *)pp->value);
201 }
202 }
203
204 if (!dryrun)
205 *pprev = NULL;
206}
207
208static int populate_node(const void *blob,
209 int offset,
210 void **mem,
211 struct device_node *dad,
212 struct device_node **pnp,
213 bool dryrun)
214{
215 struct device_node *np;
216 const char *pathp;
217 int len;
218
219 pathp = fdt_get_name(blob, offset, &len);
220 if (!pathp) {
221 *pnp = NULL;
222 return len;
223 }
224
225 len++;
226
227 np = unflatten_dt_alloc(mem, sizeof(struct device_node) + len,
228 __alignof__(struct device_node));
229 if (!dryrun) {
230 char *fn;
231 of_node_init(np);
232 np->full_name = fn = ((char *)np) + sizeof(*np);
233
234 memcpy(fn, pathp, len);
235
236 if (dad != NULL) {
237 np->parent = dad;
238 np->sibling = dad->child;
239 dad->child = np;
240 }
241 }
242
243 populate_properties(blob, offset, mem, np, pathp, dryrun);
244 if (!dryrun) {
245 np->name = of_get_property(np, "name", NULL);
246 if (!np->name)
247 np->name = "<NULL>";
248 }
249
250 *pnp = np;
251 return true;
252}
253
254static void reverse_nodes(struct device_node *parent)
255{
256 struct device_node *child, *next;
257
258 /* In-depth first */
259 child = parent->child;
260 while (child) {
261 reverse_nodes(child);
262
263 child = child->sibling;
264 }
265
266 /* Reverse the nodes in the child list */
267 child = parent->child;
268 parent->child = NULL;
269 while (child) {
270 next = child->sibling;
271
272 child->sibling = parent->child;
273 parent->child = child;
274 child = next;
275 }
276}
277
278/**
279 * unflatten_dt_nodes - Alloc and populate a device_node from the flat tree
280 * @blob: The parent device tree blob
281 * @mem: Memory chunk to use for allocating device nodes and properties
282 * @dad: Parent struct device_node
283 * @nodepp: The device_node tree created by the call
284 *
285 * Return: The size of unflattened device tree or error code
286 */
287static int unflatten_dt_nodes(const void *blob,
288 void *mem,
289 struct device_node *dad,
290 struct device_node **nodepp)
291{
292 struct device_node *root;
293 int offset = 0, depth = 0, initial_depth = 0;
294#define FDT_MAX_DEPTH 64
295 struct device_node *nps[FDT_MAX_DEPTH];
296 void *base = mem;
297 bool dryrun = !base;
298 int ret;
299
300 if (nodepp)
301 *nodepp = NULL;
302
303 /*
304 * We're unflattening device sub-tree if @dad is valid. There are
305 * possibly multiple nodes in the first level of depth. We need
306 * set @depth to 1 to make fdt_next_node() happy as it bails
307 * immediately when negative @depth is found. Otherwise, the device
308 * nodes except the first one won't be unflattened successfully.
309 */
310 if (dad)
311 depth = initial_depth = 1;
312
313 root = dad;
314 nps[depth] = dad;
315
316 for (offset = 0;
317 offset >= 0 && depth >= initial_depth;
318 offset = fdt_next_node(blob, offset, &depth)) {
319 if (WARN_ON_ONCE(depth >= FDT_MAX_DEPTH))
320 continue;
321
322 if (!IS_ENABLED(CONFIG_OF_KOBJ) &&
323 !of_fdt_device_is_available(blob, offset))
324 continue;
325
326 ret = populate_node(blob, offset, &mem, nps[depth],
327 &nps[depth+1], dryrun);
328 if (ret < 0)
329 return ret;
330
331 if (!dryrun && nodepp && !*nodepp)
332 *nodepp = nps[depth+1];
333 if (!dryrun && !root)
334 root = nps[depth+1];
335 }
336
337 if (offset < 0 && offset != -FDT_ERR_NOTFOUND) {
338 pr_err("Error %d processing FDT\n", offset);
339 return -EINVAL;
340 }
341
342 /*
343 * Reverse the child list. Some drivers assumes node order matches .dts
344 * node order
345 */
346 if (!dryrun)
347 reverse_nodes(root);
348
349 return mem - base;
350}
351
352/**
353 * __unflatten_device_tree - create tree of device_nodes from flat blob
354 * @blob: The blob to expand
355 * @dad: Parent device node
356 * @mynodes: The device_node tree created by the call
357 * @dt_alloc: An allocator that provides a virtual address to memory
358 * for the resulting tree
359 * @detached: if true set OF_DETACHED on @mynodes
360 *
361 * unflattens a device-tree, creating the tree of struct device_node. It also
362 * fills the "name" and "type" pointers of the nodes so the normal device-tree
363 * walking functions can be used.
364 *
365 * Return: NULL on failure or the memory chunk containing the unflattened
366 * device tree on success.
367 */
368void *__unflatten_device_tree(const void *blob,
369 struct device_node *dad,
370 struct device_node **mynodes,
371 void *(*dt_alloc)(u64 size, u64 align),
372 bool detached)
373{
374 int size;
375 void *mem;
376 int ret;
377
378 if (mynodes)
379 *mynodes = NULL;
380
381 pr_debug(" -> unflatten_device_tree()\n");
382
383 if (!blob) {
384 pr_debug("No device tree pointer\n");
385 return NULL;
386 }
387
388 pr_debug("Unflattening device tree:\n");
389 pr_debug("magic: %08x\n", fdt_magic(blob));
390 pr_debug("size: %08x\n", fdt_totalsize(blob));
391 pr_debug("version: %08x\n", fdt_version(blob));
392
393 if (fdt_check_header(blob)) {
394 pr_err("Invalid device tree blob header\n");
395 return NULL;
396 }
397
398 /* First pass, scan for size */
399 size = unflatten_dt_nodes(blob, NULL, dad, NULL);
400 if (size <= 0)
401 return NULL;
402
403 size = ALIGN(size, 4);
404 pr_debug(" size is %d, allocating...\n", size);
405
406 /* Allocate memory for the expanded device tree */
407 mem = dt_alloc(size + 4, __alignof__(struct device_node));
408 if (!mem)
409 return NULL;
410
411 memset(mem, 0, size);
412
413 *(__be32 *)(mem + size) = cpu_to_be32(0xdeadbeef);
414
415 pr_debug(" unflattening %p...\n", mem);
416
417 /* Second pass, do actual unflattening */
418 ret = unflatten_dt_nodes(blob, mem, dad, mynodes);
419
420 if (be32_to_cpup(mem + size) != 0xdeadbeef)
421 pr_warn("End of tree marker overwritten: %08x\n",
422 be32_to_cpup(mem + size));
423
424 if (ret <= 0)
425 return NULL;
426
427 if (detached && mynodes && *mynodes) {
428 of_node_set_flag(*mynodes, OF_DETACHED);
429 pr_debug("unflattened tree is detached\n");
430 }
431
432 pr_debug(" <- unflatten_device_tree()\n");
433 return mem;
434}
435
436static void *kernel_tree_alloc(u64 size, u64 align)
437{
438 return kzalloc(size, GFP_KERNEL);
439}
440
441static DEFINE_MUTEX(of_fdt_unflatten_mutex);
442
443/**
444 * of_fdt_unflatten_tree - create tree of device_nodes from flat blob
445 * @blob: Flat device tree blob
446 * @dad: Parent device node
447 * @mynodes: The device tree created by the call
448 *
449 * unflattens the device-tree passed by the firmware, creating the
450 * tree of struct device_node. It also fills the "name" and "type"
451 * pointers of the nodes so the normal device-tree walking functions
452 * can be used.
453 *
454 * Return: NULL on failure or the memory chunk containing the unflattened
455 * device tree on success.
456 */
457void *of_fdt_unflatten_tree(const unsigned long *blob,
458 struct device_node *dad,
459 struct device_node **mynodes)
460{
461 void *mem;
462
463 mutex_lock(&of_fdt_unflatten_mutex);
464 mem = __unflatten_device_tree(blob, dad, mynodes, &kernel_tree_alloc,
465 true);
466 mutex_unlock(&of_fdt_unflatten_mutex);
467
468 return mem;
469}
470EXPORT_SYMBOL_GPL(of_fdt_unflatten_tree);
471
472/* Everything below here references initial_boot_params directly. */
473int __initdata dt_root_addr_cells;
474int __initdata dt_root_size_cells;
475
476void *initial_boot_params __ro_after_init;
477
478#ifdef CONFIG_OF_EARLY_FLATTREE
479
480static u32 of_fdt_crc32;
481
482/*
483 * __reserved_mem_reserve_reg() - reserve all memory described in 'reg' property
484 */
485static int __init __reserved_mem_reserve_reg(unsigned long node,
486 const char *uname)
487{
488 int t_len = (dt_root_addr_cells + dt_root_size_cells) * sizeof(__be32);
489 phys_addr_t base, size;
490 int len;
491 const __be32 *prop;
492 int first = 1;
493 bool nomap;
494
495 prop = of_get_flat_dt_prop(node, "reg", &len);
496 if (!prop)
497 return -ENOENT;
498
499 if (len && len % t_len != 0) {
500 pr_err("Reserved memory: invalid reg property in '%s', skipping node.\n",
501 uname);
502 return -EINVAL;
503 }
504
505 nomap = of_get_flat_dt_prop(node, "no-map", NULL) != NULL;
506
507 while (len >= t_len) {
508 base = dt_mem_next_cell(dt_root_addr_cells, &prop);
509 size = dt_mem_next_cell(dt_root_size_cells, &prop);
510
511 if (size &&
512 early_init_dt_reserve_memory_arch(base, size, nomap) == 0)
513 pr_debug("Reserved memory: reserved region for node '%s': base %pa, size %lu MiB\n",
514 uname, &base, (unsigned long)(size / SZ_1M));
515 else
516 pr_info("Reserved memory: failed to reserve memory for node '%s': base %pa, size %lu MiB\n",
517 uname, &base, (unsigned long)(size / SZ_1M));
518
519 len -= t_len;
520 if (first) {
521 fdt_reserved_mem_save_node(node, uname, base, size);
522 first = 0;
523 }
524 }
525 return 0;
526}
527
528/*
529 * __reserved_mem_check_root() - check if #size-cells, #address-cells provided
530 * in /reserved-memory matches the values supported by the current implementation,
531 * also check if ranges property has been provided
532 */
533static int __init __reserved_mem_check_root(unsigned long node)
534{
535 const __be32 *prop;
536
537 prop = of_get_flat_dt_prop(node, "#size-cells", NULL);
538 if (!prop || be32_to_cpup(prop) != dt_root_size_cells)
539 return -EINVAL;
540
541 prop = of_get_flat_dt_prop(node, "#address-cells", NULL);
542 if (!prop || be32_to_cpup(prop) != dt_root_addr_cells)
543 return -EINVAL;
544
545 prop = of_get_flat_dt_prop(node, "ranges", NULL);
546 if (!prop)
547 return -EINVAL;
548 return 0;
549}
550
551/*
552 * __fdt_scan_reserved_mem() - scan a single FDT node for reserved memory
553 */
554static int __init __fdt_scan_reserved_mem(unsigned long node, const char *uname,
555 int depth, void *data)
556{
557 static int found;
558 int err;
559
560 if (!found && depth == 1 && strcmp(uname, "reserved-memory") == 0) {
561 if (__reserved_mem_check_root(node) != 0) {
562 pr_err("Reserved memory: unsupported node format, ignoring\n");
563 /* break scan */
564 return 1;
565 }
566 found = 1;
567 /* scan next node */
568 return 0;
569 } else if (!found) {
570 /* scan next node */
571 return 0;
572 } else if (found && depth < 2) {
573 /* scanning of /reserved-memory has been finished */
574 return 1;
575 }
576
577 if (!of_fdt_device_is_available(initial_boot_params, node))
578 return 0;
579
580 err = __reserved_mem_reserve_reg(node, uname);
581 if (err == -ENOENT && of_get_flat_dt_prop(node, "size", NULL))
582 fdt_reserved_mem_save_node(node, uname, 0, 0);
583
584 /* scan next node */
585 return 0;
586}
587
588/**
589 * early_init_fdt_scan_reserved_mem() - create reserved memory regions
590 *
591 * This function grabs memory from early allocator for device exclusive use
592 * defined in device tree structures. It should be called by arch specific code
593 * once the early allocator (i.e. memblock) has been fully activated.
594 */
595void __init early_init_fdt_scan_reserved_mem(void)
596{
597 int n;
598 u64 base, size;
599
600 if (!initial_boot_params)
601 return;
602
603 /* Process header /memreserve/ fields */
604 for (n = 0; ; n++) {
605 fdt_get_mem_rsv(initial_boot_params, n, &base, &size);
606 if (!size)
607 break;
608 early_init_dt_reserve_memory_arch(base, size, false);
609 }
610
611 of_scan_flat_dt(__fdt_scan_reserved_mem, NULL);
612 fdt_init_reserved_mem();
613}
614
615/**
616 * early_init_fdt_reserve_self() - reserve the memory used by the FDT blob
617 */
618void __init early_init_fdt_reserve_self(void)
619{
620 if (!initial_boot_params)
621 return;
622
623 /* Reserve the dtb region */
624 early_init_dt_reserve_memory_arch(__pa(initial_boot_params),
625 fdt_totalsize(initial_boot_params),
626 false);
627}
628
629/**
630 * of_scan_flat_dt - scan flattened tree blob and call callback on each.
631 * @it: callback function
632 * @data: context data pointer
633 *
634 * This function is used to scan the flattened device-tree, it is
635 * used to extract the memory information at boot before we can
636 * unflatten the tree
637 */
638int __init of_scan_flat_dt(int (*it)(unsigned long node,
639 const char *uname, int depth,
640 void *data),
641 void *data)
642{
643 const void *blob = initial_boot_params;
644 const char *pathp;
645 int offset, rc = 0, depth = -1;
646
647 if (!blob)
648 return 0;
649
650 for (offset = fdt_next_node(blob, -1, &depth);
651 offset >= 0 && depth >= 0 && !rc;
652 offset = fdt_next_node(blob, offset, &depth)) {
653
654 pathp = fdt_get_name(blob, offset, NULL);
655 rc = it(offset, pathp, depth, data);
656 }
657 return rc;
658}
659
660/**
661 * of_scan_flat_dt_subnodes - scan sub-nodes of a node call callback on each.
662 * @parent: parent node
663 * @it: callback function
664 * @data: context data pointer
665 *
666 * This function is used to scan sub-nodes of a node.
667 */
668int __init of_scan_flat_dt_subnodes(unsigned long parent,
669 int (*it)(unsigned long node,
670 const char *uname,
671 void *data),
672 void *data)
673{
674 const void *blob = initial_boot_params;
675 int node;
676
677 fdt_for_each_subnode(node, blob, parent) {
678 const char *pathp;
679 int rc;
680
681 pathp = fdt_get_name(blob, node, NULL);
682 rc = it(node, pathp, data);
683 if (rc)
684 return rc;
685 }
686 return 0;
687}
688
689/**
690 * of_get_flat_dt_subnode_by_name - get the subnode by given name
691 *
692 * @node: the parent node
693 * @uname: the name of subnode
694 * @return offset of the subnode, or -FDT_ERR_NOTFOUND if there is none
695 */
696
697int __init of_get_flat_dt_subnode_by_name(unsigned long node, const char *uname)
698{
699 return fdt_subnode_offset(initial_boot_params, node, uname);
700}
701
702/*
703 * of_get_flat_dt_root - find the root node in the flat blob
704 */
705unsigned long __init of_get_flat_dt_root(void)
706{
707 return 0;
708}
709
710/*
711 * of_get_flat_dt_prop - Given a node in the flat blob, return the property ptr
712 *
713 * This function can be used within scan_flattened_dt callback to get
714 * access to properties
715 */
716const void *__init of_get_flat_dt_prop(unsigned long node, const char *name,
717 int *size)
718{
719 return fdt_getprop(initial_boot_params, node, name, size);
720}
721
722/**
723 * of_fdt_is_compatible - Return true if given node from the given blob has
724 * compat in its compatible list
725 * @blob: A device tree blob
726 * @node: node to test
727 * @compat: compatible string to compare with compatible list.
728 *
729 * Return: a non-zero value on match with smaller values returned for more
730 * specific compatible values.
731 */
732static int of_fdt_is_compatible(const void *blob,
733 unsigned long node, const char *compat)
734{
735 const char *cp;
736 int cplen;
737 unsigned long l, score = 0;
738
739 cp = fdt_getprop(blob, node, "compatible", &cplen);
740 if (cp == NULL)
741 return 0;
742 while (cplen > 0) {
743 score++;
744 if (of_compat_cmp(cp, compat, strlen(compat)) == 0)
745 return score;
746 l = strlen(cp) + 1;
747 cp += l;
748 cplen -= l;
749 }
750
751 return 0;
752}
753
754/**
755 * of_flat_dt_is_compatible - Return true if given node has compat in compatible list
756 * @node: node to test
757 * @compat: compatible string to compare with compatible list.
758 */
759int __init of_flat_dt_is_compatible(unsigned long node, const char *compat)
760{
761 return of_fdt_is_compatible(initial_boot_params, node, compat);
762}
763
764/*
765 * of_flat_dt_match - Return true if node matches a list of compatible values
766 */
767static int __init of_flat_dt_match(unsigned long node, const char *const *compat)
768{
769 unsigned int tmp, score = 0;
770
771 if (!compat)
772 return 0;
773
774 while (*compat) {
775 tmp = of_fdt_is_compatible(initial_boot_params, node, *compat);
776 if (tmp && (score == 0 || (tmp < score)))
777 score = tmp;
778 compat++;
779 }
780
781 return score;
782}
783
784/*
785 * of_get_flat_dt_phandle - Given a node in the flat blob, return the phandle
786 */
787uint32_t __init of_get_flat_dt_phandle(unsigned long node)
788{
789 return fdt_get_phandle(initial_boot_params, node);
790}
791
792struct fdt_scan_status {
793 const char *name;
794 int namelen;
795 int depth;
796 int found;
797 int (*iterator)(unsigned long node, const char *uname, int depth, void *data);
798 void *data;
799};
800
801const char * __init of_flat_dt_get_machine_name(void)
802{
803 const char *name;
804 unsigned long dt_root = of_get_flat_dt_root();
805
806 name = of_get_flat_dt_prop(dt_root, "model", NULL);
807 if (!name)
808 name = of_get_flat_dt_prop(dt_root, "compatible", NULL);
809 return name;
810}
811
812/**
813 * of_flat_dt_match_machine - Iterate match tables to find matching machine.
814 *
815 * @default_match: A machine specific ptr to return in case of no match.
816 * @get_next_compat: callback function to return next compatible match table.
817 *
818 * Iterate through machine match tables to find the best match for the machine
819 * compatible string in the FDT.
820 */
821const void * __init of_flat_dt_match_machine(const void *default_match,
822 const void * (*get_next_compat)(const char * const**))
823{
824 const void *data = NULL;
825 const void *best_data = default_match;
826 const char *const *compat;
827 unsigned long dt_root;
828 unsigned int best_score = ~1, score = 0;
829
830 dt_root = of_get_flat_dt_root();
831 while ((data = get_next_compat(&compat))) {
832 score = of_flat_dt_match(dt_root, compat);
833 if (score > 0 && score < best_score) {
834 best_data = data;
835 best_score = score;
836 }
837 }
838 if (!best_data) {
839 const char *prop;
840 int size;
841
842 pr_err("\n unrecognized device tree list:\n[ ");
843
844 prop = of_get_flat_dt_prop(dt_root, "compatible", &size);
845 if (prop) {
846 while (size > 0) {
847 printk("'%s' ", prop);
848 size -= strlen(prop) + 1;
849 prop += strlen(prop) + 1;
850 }
851 }
852 printk("]\n\n");
853 return NULL;
854 }
855
856 pr_info("Machine model: %s\n", of_flat_dt_get_machine_name());
857
858 return best_data;
859}
860
861#ifdef CONFIG_BLK_DEV_INITRD
862static void __early_init_dt_declare_initrd(unsigned long start,
863 unsigned long end)
864{
865 /* ARM64 would cause a BUG to occur here when CONFIG_DEBUG_VM is
866 * enabled since __va() is called too early. ARM64 does make use
867 * of phys_initrd_start/phys_initrd_size so we can skip this
868 * conversion.
869 */
870 if (!IS_ENABLED(CONFIG_ARM64)) {
871 initrd_start = (unsigned long)__va(start);
872 initrd_end = (unsigned long)__va(end);
873 initrd_below_start_ok = 1;
874 }
875}
876
877/**
878 * early_init_dt_check_for_initrd - Decode initrd location from flat tree
879 * @node: reference to node containing initrd location ('chosen')
880 */
881static void __init early_init_dt_check_for_initrd(unsigned long node)
882{
883 u64 start, end;
884 int len;
885 const __be32 *prop;
886
887 pr_debug("Looking for initrd properties... ");
888
889 prop = of_get_flat_dt_prop(node, "linux,initrd-start", &len);
890 if (!prop)
891 return;
892 start = of_read_number(prop, len/4);
893
894 prop = of_get_flat_dt_prop(node, "linux,initrd-end", &len);
895 if (!prop)
896 return;
897 end = of_read_number(prop, len/4);
898
899 __early_init_dt_declare_initrd(start, end);
900 phys_initrd_start = start;
901 phys_initrd_size = end - start;
902
903 pr_debug("initrd_start=0x%llx initrd_end=0x%llx\n", start, end);
904}
905#else
906static inline void early_init_dt_check_for_initrd(unsigned long node)
907{
908}
909#endif /* CONFIG_BLK_DEV_INITRD */
910
911#ifdef CONFIG_SERIAL_EARLYCON
912
913int __init early_init_dt_scan_chosen_stdout(void)
914{
915 int offset;
916 const char *p, *q, *options = NULL;
917 int l;
918 const struct earlycon_id *match;
919 const void *fdt = initial_boot_params;
920
921 offset = fdt_path_offset(fdt, "/chosen");
922 if (offset < 0)
923 offset = fdt_path_offset(fdt, "/chosen@0");
924 if (offset < 0)
925 return -ENOENT;
926
927 p = fdt_getprop(fdt, offset, "stdout-path", &l);
928 if (!p)
929 p = fdt_getprop(fdt, offset, "linux,stdout-path", &l);
930 if (!p || !l)
931 return -ENOENT;
932
933 q = strchrnul(p, ':');
934 if (*q != '\0')
935 options = q + 1;
936 l = q - p;
937
938 /* Get the node specified by stdout-path */
939 offset = fdt_path_offset_namelen(fdt, p, l);
940 if (offset < 0) {
941 pr_warn("earlycon: stdout-path %.*s not found\n", l, p);
942 return 0;
943 }
944
945 for (match = __earlycon_table; match < __earlycon_table_end; match++) {
946 if (!match->compatible[0])
947 continue;
948
949 if (fdt_node_check_compatible(fdt, offset, match->compatible))
950 continue;
951
952 if (of_setup_earlycon(match, offset, options) == 0)
953 return 0;
954 }
955 return -ENODEV;
956}
957#endif
958
959/*
960 * early_init_dt_scan_root - fetch the top level address and size cells
961 */
962int __init early_init_dt_scan_root(unsigned long node, const char *uname,
963 int depth, void *data)
964{
965 const __be32 *prop;
966
967 if (depth != 0)
968 return 0;
969
970 dt_root_size_cells = OF_ROOT_NODE_SIZE_CELLS_DEFAULT;
971 dt_root_addr_cells = OF_ROOT_NODE_ADDR_CELLS_DEFAULT;
972
973 prop = of_get_flat_dt_prop(node, "#size-cells", NULL);
974 if (prop)
975 dt_root_size_cells = be32_to_cpup(prop);
976 pr_debug("dt_root_size_cells = %x\n", dt_root_size_cells);
977
978 prop = of_get_flat_dt_prop(node, "#address-cells", NULL);
979 if (prop)
980 dt_root_addr_cells = be32_to_cpup(prop);
981 pr_debug("dt_root_addr_cells = %x\n", dt_root_addr_cells);
982
983 /* break now */
984 return 1;
985}
986
987u64 __init dt_mem_next_cell(int s, const __be32 **cellp)
988{
989 const __be32 *p = *cellp;
990
991 *cellp = p + s;
992 return of_read_number(p, s);
993}
994
995/*
996 * early_init_dt_scan_memory - Look for and parse memory nodes
997 */
998int __init early_init_dt_scan_memory(unsigned long node, const char *uname,
999 int depth, void *data)
1000{
1001 const char *type = of_get_flat_dt_prop(node, "device_type", NULL);
1002 const __be32 *reg, *endp;
1003 int l;
1004 bool hotpluggable;
1005
1006 /* We are scanning "memory" nodes only */
1007 if (type == NULL || strcmp(type, "memory") != 0)
1008 return 0;
1009
1010 reg = of_get_flat_dt_prop(node, "linux,usable-memory", &l);
1011 if (reg == NULL)
1012 reg = of_get_flat_dt_prop(node, "reg", &l);
1013 if (reg == NULL)
1014 return 0;
1015
1016 endp = reg + (l / sizeof(__be32));
1017 hotpluggable = of_get_flat_dt_prop(node, "hotpluggable", NULL);
1018
1019 pr_debug("memory scan node %s, reg size %d,\n", uname, l);
1020
1021 while ((endp - reg) >= (dt_root_addr_cells + dt_root_size_cells)) {
1022 u64 base, size;
1023
1024 base = dt_mem_next_cell(dt_root_addr_cells, ®);
1025 size = dt_mem_next_cell(dt_root_size_cells, ®);
1026
1027 if (size == 0)
1028 continue;
1029 pr_debug(" - %llx, %llx\n", base, size);
1030
1031 early_init_dt_add_memory_arch(base, size);
1032
1033 if (!hotpluggable)
1034 continue;
1035
1036 if (early_init_dt_mark_hotplug_memory_arch(base, size))
1037 pr_warn("failed to mark hotplug range 0x%llx - 0x%llx\n",
1038 base, base + size);
1039 }
1040
1041 return 0;
1042}
1043
1044int __init early_init_dt_scan_chosen(unsigned long node, const char *uname,
1045 int depth, void *data)
1046{
1047 int l;
1048 const char *p;
1049 const void *rng_seed;
1050
1051 pr_debug("search \"chosen\", depth: %d, uname: %s\n", depth, uname);
1052
1053 if (depth != 1 || !data ||
1054 (strcmp(uname, "chosen") != 0 && strcmp(uname, "chosen@0") != 0))
1055 return 0;
1056
1057 early_init_dt_check_for_initrd(node);
1058
1059 /* Retrieve command line */
1060 p = of_get_flat_dt_prop(node, "bootargs", &l);
1061 if (p != NULL && l > 0)
1062 strlcpy(data, p, min(l, COMMAND_LINE_SIZE));
1063
1064 /*
1065 * CONFIG_CMDLINE is meant to be a default in case nothing else
1066 * managed to set the command line, unless CONFIG_CMDLINE_FORCE
1067 * is set in which case we override whatever was found earlier.
1068 */
1069#ifdef CONFIG_CMDLINE
1070#if defined(CONFIG_CMDLINE_EXTEND)
1071 strlcat(data, " ", COMMAND_LINE_SIZE);
1072 strlcat(data, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
1073#elif defined(CONFIG_CMDLINE_FORCE)
1074 strlcpy(data, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
1075#else
1076 /* No arguments from boot loader, use kernel's cmdl*/
1077 if (!((char *)data)[0])
1078 strlcpy(data, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
1079#endif
1080#endif /* CONFIG_CMDLINE */
1081
1082 pr_debug("Command line is: %s\n", (char *)data);
1083
1084 rng_seed = of_get_flat_dt_prop(node, "rng-seed", &l);
1085 if (rng_seed && l > 0) {
1086 add_bootloader_randomness(rng_seed, l);
1087
1088 /* try to clear seed so it won't be found. */
1089 fdt_nop_property(initial_boot_params, node, "rng-seed");
1090
1091 /* update CRC check value */
1092 of_fdt_crc32 = crc32_be(~0, initial_boot_params,
1093 fdt_totalsize(initial_boot_params));
1094 }
1095
1096 /* break now */
1097 return 1;
1098}
1099
1100#ifndef MIN_MEMBLOCK_ADDR
1101#define MIN_MEMBLOCK_ADDR __pa(PAGE_OFFSET)
1102#endif
1103#ifndef MAX_MEMBLOCK_ADDR
1104#define MAX_MEMBLOCK_ADDR ((phys_addr_t)~0)
1105#endif
1106
1107void __init __weak early_init_dt_add_memory_arch(u64 base, u64 size)
1108{
1109 const u64 phys_offset = MIN_MEMBLOCK_ADDR;
1110
1111 if (size < PAGE_SIZE - (base & ~PAGE_MASK)) {
1112 pr_warn("Ignoring memory block 0x%llx - 0x%llx\n",
1113 base, base + size);
1114 return;
1115 }
1116
1117 if (!PAGE_ALIGNED(base)) {
1118 size -= PAGE_SIZE - (base & ~PAGE_MASK);
1119 base = PAGE_ALIGN(base);
1120 }
1121 size &= PAGE_MASK;
1122
1123 if (base > MAX_MEMBLOCK_ADDR) {
1124 pr_warn("Ignoring memory block 0x%llx - 0x%llx\n",
1125 base, base + size);
1126 return;
1127 }
1128
1129 if (base + size - 1 > MAX_MEMBLOCK_ADDR) {
1130 pr_warn("Ignoring memory range 0x%llx - 0x%llx\n",
1131 ((u64)MAX_MEMBLOCK_ADDR) + 1, base + size);
1132 size = MAX_MEMBLOCK_ADDR - base + 1;
1133 }
1134
1135 if (base + size < phys_offset) {
1136 pr_warn("Ignoring memory block 0x%llx - 0x%llx\n",
1137 base, base + size);
1138 return;
1139 }
1140 if (base < phys_offset) {
1141 pr_warn("Ignoring memory range 0x%llx - 0x%llx\n",
1142 base, phys_offset);
1143 size -= phys_offset - base;
1144 base = phys_offset;
1145 }
1146 memblock_add(base, size);
1147}
1148
1149int __init __weak early_init_dt_mark_hotplug_memory_arch(u64 base, u64 size)
1150{
1151 return memblock_mark_hotplug(base, size);
1152}
1153
1154int __init __weak early_init_dt_reserve_memory_arch(phys_addr_t base,
1155 phys_addr_t size, bool nomap)
1156{
1157 if (nomap) {
1158 /*
1159 * If the memory is already reserved (by another region), we
1160 * should not allow it to be marked nomap.
1161 */
1162 if (memblock_is_region_reserved(base, size))
1163 return -EBUSY;
1164
1165 return memblock_mark_nomap(base, size);
1166 }
1167 return memblock_reserve(base, size);
1168}
1169
1170static void * __init early_init_dt_alloc_memory_arch(u64 size, u64 align)
1171{
1172 void *ptr = memblock_alloc(size, align);
1173
1174 if (!ptr)
1175 panic("%s: Failed to allocate %llu bytes align=0x%llx\n",
1176 __func__, size, align);
1177
1178 return ptr;
1179}
1180
1181bool __init early_init_dt_verify(void *params)
1182{
1183 if (!params)
1184 return false;
1185
1186 /* check device tree validity */
1187 if (fdt_check_header(params))
1188 return false;
1189
1190 /* Setup flat device-tree pointer */
1191 initial_boot_params = params;
1192 of_fdt_crc32 = crc32_be(~0, initial_boot_params,
1193 fdt_totalsize(initial_boot_params));
1194 return true;
1195}
1196
1197
1198void __init early_init_dt_scan_nodes(void)
1199{
1200 int rc = 0;
1201
1202 /* Retrieve various information from the /chosen node */
1203 rc = of_scan_flat_dt(early_init_dt_scan_chosen, boot_command_line);
1204 if (!rc)
1205 pr_warn("No chosen node found, continuing without\n");
1206
1207 /* Initialize {size,address}-cells info */
1208 of_scan_flat_dt(early_init_dt_scan_root, NULL);
1209
1210 /* Setup memory, calling early_init_dt_add_memory_arch */
1211 of_scan_flat_dt(early_init_dt_scan_memory, NULL);
1212}
1213
1214bool __init early_init_dt_scan(void *params)
1215{
1216 bool status;
1217
1218 status = early_init_dt_verify(params);
1219 if (!status)
1220 return false;
1221
1222 early_init_dt_scan_nodes();
1223 return true;
1224}
1225
1226/**
1227 * unflatten_device_tree - create tree of device_nodes from flat blob
1228 *
1229 * unflattens the device-tree passed by the firmware, creating the
1230 * tree of struct device_node. It also fills the "name" and "type"
1231 * pointers of the nodes so the normal device-tree walking functions
1232 * can be used.
1233 */
1234void __init unflatten_device_tree(void)
1235{
1236 __unflatten_device_tree(initial_boot_params, NULL, &of_root,
1237 early_init_dt_alloc_memory_arch, false);
1238
1239 /* Get pointer to "/chosen" and "/aliases" nodes for use everywhere */
1240 of_alias_scan(early_init_dt_alloc_memory_arch);
1241
1242 unittest_unflatten_overlay_base();
1243}
1244
1245/**
1246 * unflatten_and_copy_device_tree - copy and create tree of device_nodes from flat blob
1247 *
1248 * Copies and unflattens the device-tree passed by the firmware, creating the
1249 * tree of struct device_node. It also fills the "name" and "type"
1250 * pointers of the nodes so the normal device-tree walking functions
1251 * can be used. This should only be used when the FDT memory has not been
1252 * reserved such is the case when the FDT is built-in to the kernel init
1253 * section. If the FDT memory is reserved already then unflatten_device_tree
1254 * should be used instead.
1255 */
1256void __init unflatten_and_copy_device_tree(void)
1257{
1258 int size;
1259 void *dt;
1260
1261 if (!initial_boot_params) {
1262 pr_warn("No valid device tree found, continuing without\n");
1263 return;
1264 }
1265
1266 size = fdt_totalsize(initial_boot_params);
1267 dt = early_init_dt_alloc_memory_arch(size,
1268 roundup_pow_of_two(FDT_V17_SIZE));
1269
1270 if (dt) {
1271 memcpy(dt, initial_boot_params, size);
1272 initial_boot_params = dt;
1273 }
1274 unflatten_device_tree();
1275}
1276
1277#ifdef CONFIG_SYSFS
1278static ssize_t of_fdt_raw_read(struct file *filp, struct kobject *kobj,
1279 struct bin_attribute *bin_attr,
1280 char *buf, loff_t off, size_t count)
1281{
1282 memcpy(buf, initial_boot_params + off, count);
1283 return count;
1284}
1285
1286static int __init of_fdt_raw_init(void)
1287{
1288 static struct bin_attribute of_fdt_raw_attr =
1289 __BIN_ATTR(fdt, S_IRUSR, of_fdt_raw_read, NULL, 0);
1290
1291 if (!initial_boot_params)
1292 return 0;
1293
1294 if (of_fdt_crc32 != crc32_be(~0, initial_boot_params,
1295 fdt_totalsize(initial_boot_params))) {
1296 pr_warn("not creating '/sys/firmware/fdt': CRC check failed\n");
1297 return 0;
1298 }
1299 of_fdt_raw_attr.size = fdt_totalsize(initial_boot_params);
1300 return sysfs_create_bin_file(firmware_kobj, &of_fdt_raw_attr);
1301}
1302late_initcall(of_fdt_raw_init);
1303#endif
1304
1305#endif /* CONFIG_OF_EARLY_FLATTREE */