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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#include <asm/setup.h> /* for COMMAND_LINE_SIZE */
22#ifdef CONFIG_PPC
23#include <asm/machdep.h>
24#endif /* CONFIG_PPC */
25
26#include <asm/page.h>
27
28char *of_fdt_get_string(struct boot_param_header *blob, u32 offset)
29{
30 return ((char *)blob) +
31 be32_to_cpu(blob->off_dt_strings) + offset;
32}
33
34/**
35 * of_fdt_get_property - Given a node in the given flat blob, return
36 * the property ptr
37 */
38void *of_fdt_get_property(struct boot_param_header *blob,
39 unsigned long node, const char *name,
40 unsigned long *size)
41{
42 unsigned long p = node;
43
44 do {
45 u32 tag = be32_to_cpup((__be32 *)p);
46 u32 sz, noff;
47 const char *nstr;
48
49 p += 4;
50 if (tag == OF_DT_NOP)
51 continue;
52 if (tag != OF_DT_PROP)
53 return NULL;
54
55 sz = be32_to_cpup((__be32 *)p);
56 noff = be32_to_cpup((__be32 *)(p + 4));
57 p += 8;
58 if (be32_to_cpu(blob->version) < 0x10)
59 p = ALIGN(p, sz >= 8 ? 8 : 4);
60
61 nstr = of_fdt_get_string(blob, noff);
62 if (nstr == NULL) {
63 pr_warning("Can't find property index name !\n");
64 return NULL;
65 }
66 if (strcmp(name, nstr) == 0) {
67 if (size)
68 *size = sz;
69 return (void *)p;
70 }
71 p += sz;
72 p = ALIGN(p, 4);
73 } while (1);
74}
75
76/**
77 * of_fdt_is_compatible - Return true if given node from the given blob has
78 * compat in its compatible list
79 * @blob: A device tree blob
80 * @node: node to test
81 * @compat: compatible string to compare with compatible list.
82 *
83 * On match, returns a non-zero value with smaller values returned for more
84 * specific compatible values.
85 */
86int of_fdt_is_compatible(struct boot_param_header *blob,
87 unsigned long node, const char *compat)
88{
89 const char *cp;
90 unsigned long cplen, l, score = 0;
91
92 cp = of_fdt_get_property(blob, node, "compatible", &cplen);
93 if (cp == NULL)
94 return 0;
95 while (cplen > 0) {
96 score++;
97 if (of_compat_cmp(cp, compat, strlen(compat)) == 0)
98 return score;
99 l = strlen(cp) + 1;
100 cp += l;
101 cplen -= l;
102 }
103
104 return 0;
105}
106
107/**
108 * of_fdt_match - Return true if node matches a list of compatible values
109 */
110int of_fdt_match(struct boot_param_header *blob, unsigned long node,
111 const char *const *compat)
112{
113 unsigned int tmp, score = 0;
114
115 if (!compat)
116 return 0;
117
118 while (*compat) {
119 tmp = of_fdt_is_compatible(blob, node, *compat);
120 if (tmp && (score == 0 || (tmp < score)))
121 score = tmp;
122 compat++;
123 }
124
125 return score;
126}
127
128static void *unflatten_dt_alloc(unsigned long *mem, unsigned long size,
129 unsigned long align)
130{
131 void *res;
132
133 *mem = ALIGN(*mem, align);
134 res = (void *)*mem;
135 *mem += size;
136
137 return res;
138}
139
140/**
141 * unflatten_dt_node - Alloc and populate a device_node from the flat tree
142 * @blob: The parent device tree blob
143 * @mem: Memory chunk to use for allocating device nodes and properties
144 * @p: pointer to node in flat tree
145 * @dad: Parent struct device_node
146 * @allnextpp: pointer to ->allnext from last allocated device_node
147 * @fpsize: Size of the node path up at the current depth.
148 */
149static unsigned long unflatten_dt_node(struct boot_param_header *blob,
150 unsigned long mem,
151 unsigned long *p,
152 struct device_node *dad,
153 struct device_node ***allnextpp,
154 unsigned long fpsize)
155{
156 struct device_node *np;
157 struct property *pp, **prev_pp = NULL;
158 char *pathp;
159 u32 tag;
160 unsigned int l, allocl;
161 int has_name = 0;
162 int new_format = 0;
163
164 tag = be32_to_cpup((__be32 *)(*p));
165 if (tag != OF_DT_BEGIN_NODE) {
166 pr_err("Weird tag at start of node: %x\n", tag);
167 return mem;
168 }
169 *p += 4;
170 pathp = (char *)*p;
171 l = allocl = strlen(pathp) + 1;
172 *p = ALIGN(*p + l, 4);
173
174 /* version 0x10 has a more compact unit name here instead of the full
175 * path. we accumulate the full path size using "fpsize", we'll rebuild
176 * it later. We detect this because the first character of the name is
177 * not '/'.
178 */
179 if ((*pathp) != '/') {
180 new_format = 1;
181 if (fpsize == 0) {
182 /* root node: special case. fpsize accounts for path
183 * plus terminating zero. root node only has '/', so
184 * fpsize should be 2, but we want to avoid the first
185 * level nodes to have two '/' so we use fpsize 1 here
186 */
187 fpsize = 1;
188 allocl = 2;
189 } else {
190 /* account for '/' and path size minus terminal 0
191 * already in 'l'
192 */
193 fpsize += l;
194 allocl = fpsize;
195 }
196 }
197
198 np = unflatten_dt_alloc(&mem, sizeof(struct device_node) + allocl,
199 __alignof__(struct device_node));
200 if (allnextpp) {
201 memset(np, 0, sizeof(*np));
202 np->full_name = ((char *)np) + sizeof(struct device_node);
203 if (new_format) {
204 char *fn = np->full_name;
205 /* rebuild full path for new format */
206 if (dad && dad->parent) {
207 strcpy(fn, dad->full_name);
208#ifdef DEBUG
209 if ((strlen(fn) + l + 1) != allocl) {
210 pr_debug("%s: p: %d, l: %d, a: %d\n",
211 pathp, (int)strlen(fn),
212 l, allocl);
213 }
214#endif
215 fn += strlen(fn);
216 }
217 *(fn++) = '/';
218 memcpy(fn, pathp, l);
219 } else
220 memcpy(np->full_name, pathp, l);
221 prev_pp = &np->properties;
222 **allnextpp = np;
223 *allnextpp = &np->allnext;
224 if (dad != NULL) {
225 np->parent = dad;
226 /* we temporarily use the next field as `last_child'*/
227 if (dad->next == NULL)
228 dad->child = np;
229 else
230 dad->next->sibling = np;
231 dad->next = np;
232 }
233 kref_init(&np->kref);
234 }
235 /* process properties */
236 while (1) {
237 u32 sz, noff;
238 char *pname;
239
240 tag = be32_to_cpup((__be32 *)(*p));
241 if (tag == OF_DT_NOP) {
242 *p += 4;
243 continue;
244 }
245 if (tag != OF_DT_PROP)
246 break;
247 *p += 4;
248 sz = be32_to_cpup((__be32 *)(*p));
249 noff = be32_to_cpup((__be32 *)((*p) + 4));
250 *p += 8;
251 if (be32_to_cpu(blob->version) < 0x10)
252 *p = ALIGN(*p, sz >= 8 ? 8 : 4);
253
254 pname = of_fdt_get_string(blob, noff);
255 if (pname == NULL) {
256 pr_info("Can't find property name in list !\n");
257 break;
258 }
259 if (strcmp(pname, "name") == 0)
260 has_name = 1;
261 l = strlen(pname) + 1;
262 pp = unflatten_dt_alloc(&mem, sizeof(struct property),
263 __alignof__(struct property));
264 if (allnextpp) {
265 /* We accept flattened tree phandles either in
266 * ePAPR-style "phandle" properties, or the
267 * legacy "linux,phandle" properties. If both
268 * appear and have different values, things
269 * will get weird. Don't do that. */
270 if ((strcmp(pname, "phandle") == 0) ||
271 (strcmp(pname, "linux,phandle") == 0)) {
272 if (np->phandle == 0)
273 np->phandle = be32_to_cpup((__be32*)*p);
274 }
275 /* And we process the "ibm,phandle" property
276 * used in pSeries dynamic device tree
277 * stuff */
278 if (strcmp(pname, "ibm,phandle") == 0)
279 np->phandle = be32_to_cpup((__be32 *)*p);
280 pp->name = pname;
281 pp->length = sz;
282 pp->value = (void *)*p;
283 *prev_pp = pp;
284 prev_pp = &pp->next;
285 }
286 *p = ALIGN((*p) + sz, 4);
287 }
288 /* with version 0x10 we may not have the name property, recreate
289 * it here from the unit name if absent
290 */
291 if (!has_name) {
292 char *p1 = pathp, *ps = pathp, *pa = NULL;
293 int sz;
294
295 while (*p1) {
296 if ((*p1) == '@')
297 pa = p1;
298 if ((*p1) == '/')
299 ps = p1 + 1;
300 p1++;
301 }
302 if (pa < ps)
303 pa = p1;
304 sz = (pa - ps) + 1;
305 pp = unflatten_dt_alloc(&mem, sizeof(struct property) + sz,
306 __alignof__(struct property));
307 if (allnextpp) {
308 pp->name = "name";
309 pp->length = sz;
310 pp->value = pp + 1;
311 *prev_pp = pp;
312 prev_pp = &pp->next;
313 memcpy(pp->value, ps, sz - 1);
314 ((char *)pp->value)[sz - 1] = 0;
315 pr_debug("fixed up name for %s -> %s\n", pathp,
316 (char *)pp->value);
317 }
318 }
319 if (allnextpp) {
320 *prev_pp = NULL;
321 np->name = of_get_property(np, "name", NULL);
322 np->type = of_get_property(np, "device_type", NULL);
323
324 if (!np->name)
325 np->name = "<NULL>";
326 if (!np->type)
327 np->type = "<NULL>";
328 }
329 while (tag == OF_DT_BEGIN_NODE || tag == OF_DT_NOP) {
330 if (tag == OF_DT_NOP)
331 *p += 4;
332 else
333 mem = unflatten_dt_node(blob, mem, p, np, allnextpp,
334 fpsize);
335 tag = be32_to_cpup((__be32 *)(*p));
336 }
337 if (tag != OF_DT_END_NODE) {
338 pr_err("Weird tag at end of node: %x\n", tag);
339 return mem;
340 }
341 *p += 4;
342 return mem;
343}
344
345/**
346 * __unflatten_device_tree - create tree of device_nodes from flat blob
347 *
348 * unflattens a device-tree, creating the
349 * tree of struct device_node. It also fills the "name" and "type"
350 * pointers of the nodes so the normal device-tree walking functions
351 * can be used.
352 * @blob: The blob to expand
353 * @mynodes: The device_node tree created by the call
354 * @dt_alloc: An allocator that provides a virtual address to memory
355 * for the resulting tree
356 */
357static void __unflatten_device_tree(struct boot_param_header *blob,
358 struct device_node **mynodes,
359 void * (*dt_alloc)(u64 size, u64 align))
360{
361 unsigned long start, mem, size;
362 struct device_node **allnextp = mynodes;
363
364 pr_debug(" -> unflatten_device_tree()\n");
365
366 if (!blob) {
367 pr_debug("No device tree pointer\n");
368 return;
369 }
370
371 pr_debug("Unflattening device tree:\n");
372 pr_debug("magic: %08x\n", be32_to_cpu(blob->magic));
373 pr_debug("size: %08x\n", be32_to_cpu(blob->totalsize));
374 pr_debug("version: %08x\n", be32_to_cpu(blob->version));
375
376 if (be32_to_cpu(blob->magic) != OF_DT_HEADER) {
377 pr_err("Invalid device tree blob header\n");
378 return;
379 }
380
381 /* First pass, scan for size */
382 start = ((unsigned long)blob) +
383 be32_to_cpu(blob->off_dt_struct);
384 size = unflatten_dt_node(blob, 0, &start, NULL, NULL, 0);
385 size = (size | 3) + 1;
386
387 pr_debug(" size is %lx, allocating...\n", size);
388
389 /* Allocate memory for the expanded device tree */
390 mem = (unsigned long)
391 dt_alloc(size + 4, __alignof__(struct device_node));
392
393 ((__be32 *)mem)[size / 4] = cpu_to_be32(0xdeadbeef);
394
395 pr_debug(" unflattening %lx...\n", mem);
396
397 /* Second pass, do actual unflattening */
398 start = ((unsigned long)blob) +
399 be32_to_cpu(blob->off_dt_struct);
400 unflatten_dt_node(blob, mem, &start, NULL, &allnextp, 0);
401 if (be32_to_cpup((__be32 *)start) != OF_DT_END)
402 pr_warning("Weird tag at end of tree: %08x\n", *((u32 *)start));
403 if (be32_to_cpu(((__be32 *)mem)[size / 4]) != 0xdeadbeef)
404 pr_warning("End of tree marker overwritten: %08x\n",
405 be32_to_cpu(((__be32 *)mem)[size / 4]));
406 *allnextp = NULL;
407
408 pr_debug(" <- unflatten_device_tree()\n");
409}
410
411static void *kernel_tree_alloc(u64 size, u64 align)
412{
413 return kzalloc(size, GFP_KERNEL);
414}
415
416/**
417 * of_fdt_unflatten_tree - create tree of device_nodes from flat blob
418 *
419 * unflattens the device-tree passed by the firmware, creating the
420 * tree of struct device_node. It also fills the "name" and "type"
421 * pointers of the nodes so the normal device-tree walking functions
422 * can be used.
423 */
424void of_fdt_unflatten_tree(unsigned long *blob,
425 struct device_node **mynodes)
426{
427 struct boot_param_header *device_tree =
428 (struct boot_param_header *)blob;
429 __unflatten_device_tree(device_tree, mynodes, &kernel_tree_alloc);
430}
431EXPORT_SYMBOL_GPL(of_fdt_unflatten_tree);
432
433/* Everything below here references initial_boot_params directly. */
434int __initdata dt_root_addr_cells;
435int __initdata dt_root_size_cells;
436
437struct boot_param_header *initial_boot_params;
438
439#ifdef CONFIG_OF_EARLY_FLATTREE
440
441/**
442 * of_scan_flat_dt - scan flattened tree blob and call callback on each.
443 * @it: callback function
444 * @data: context data pointer
445 *
446 * This function is used to scan the flattened device-tree, it is
447 * used to extract the memory information at boot before we can
448 * unflatten the tree
449 */
450int __init of_scan_flat_dt(int (*it)(unsigned long node,
451 const char *uname, int depth,
452 void *data),
453 void *data)
454{
455 unsigned long p = ((unsigned long)initial_boot_params) +
456 be32_to_cpu(initial_boot_params->off_dt_struct);
457 int rc = 0;
458 int depth = -1;
459
460 do {
461 u32 tag = be32_to_cpup((__be32 *)p);
462 char *pathp;
463
464 p += 4;
465 if (tag == OF_DT_END_NODE) {
466 depth--;
467 continue;
468 }
469 if (tag == OF_DT_NOP)
470 continue;
471 if (tag == OF_DT_END)
472 break;
473 if (tag == OF_DT_PROP) {
474 u32 sz = be32_to_cpup((__be32 *)p);
475 p += 8;
476 if (be32_to_cpu(initial_boot_params->version) < 0x10)
477 p = ALIGN(p, sz >= 8 ? 8 : 4);
478 p += sz;
479 p = ALIGN(p, 4);
480 continue;
481 }
482 if (tag != OF_DT_BEGIN_NODE) {
483 pr_err("Invalid tag %x in flat device tree!\n", tag);
484 return -EINVAL;
485 }
486 depth++;
487 pathp = (char *)p;
488 p = ALIGN(p + strlen(pathp) + 1, 4);
489 if ((*pathp) == '/') {
490 char *lp, *np;
491 for (lp = NULL, np = pathp; *np; np++)
492 if ((*np) == '/')
493 lp = np+1;
494 if (lp != NULL)
495 pathp = lp;
496 }
497 rc = it(p, pathp, depth, data);
498 if (rc != 0)
499 break;
500 } while (1);
501
502 return rc;
503}
504
505/**
506 * of_get_flat_dt_root - find the root node in the flat blob
507 */
508unsigned long __init of_get_flat_dt_root(void)
509{
510 unsigned long p = ((unsigned long)initial_boot_params) +
511 be32_to_cpu(initial_boot_params->off_dt_struct);
512
513 while (be32_to_cpup((__be32 *)p) == OF_DT_NOP)
514 p += 4;
515 BUG_ON(be32_to_cpup((__be32 *)p) != OF_DT_BEGIN_NODE);
516 p += 4;
517 return ALIGN(p + strlen((char *)p) + 1, 4);
518}
519
520/**
521 * of_get_flat_dt_prop - Given a node in the flat blob, return the property ptr
522 *
523 * This function can be used within scan_flattened_dt callback to get
524 * access to properties
525 */
526void *__init of_get_flat_dt_prop(unsigned long node, const char *name,
527 unsigned long *size)
528{
529 return of_fdt_get_property(initial_boot_params, node, name, size);
530}
531
532/**
533 * of_flat_dt_is_compatible - Return true if given node has compat in compatible list
534 * @node: node to test
535 * @compat: compatible string to compare with compatible list.
536 */
537int __init of_flat_dt_is_compatible(unsigned long node, const char *compat)
538{
539 return of_fdt_is_compatible(initial_boot_params, node, compat);
540}
541
542/**
543 * of_flat_dt_match - Return true if node matches a list of compatible values
544 */
545int __init of_flat_dt_match(unsigned long node, const char *const *compat)
546{
547 return of_fdt_match(initial_boot_params, node, compat);
548}
549
550#ifdef CONFIG_BLK_DEV_INITRD
551/**
552 * early_init_dt_check_for_initrd - Decode initrd location from flat tree
553 * @node: reference to node containing initrd location ('chosen')
554 */
555void __init early_init_dt_check_for_initrd(unsigned long node)
556{
557 unsigned long start, end, len;
558 __be32 *prop;
559
560 pr_debug("Looking for initrd properties... ");
561
562 prop = of_get_flat_dt_prop(node, "linux,initrd-start", &len);
563 if (!prop)
564 return;
565 start = of_read_ulong(prop, len/4);
566
567 prop = of_get_flat_dt_prop(node, "linux,initrd-end", &len);
568 if (!prop)
569 return;
570 end = of_read_ulong(prop, len/4);
571
572 early_init_dt_setup_initrd_arch(start, end);
573 pr_debug("initrd_start=0x%lx initrd_end=0x%lx\n", start, end);
574}
575#else
576inline void early_init_dt_check_for_initrd(unsigned long node)
577{
578}
579#endif /* CONFIG_BLK_DEV_INITRD */
580
581/**
582 * early_init_dt_scan_root - fetch the top level address and size cells
583 */
584int __init early_init_dt_scan_root(unsigned long node, const char *uname,
585 int depth, void *data)
586{
587 __be32 *prop;
588
589 if (depth != 0)
590 return 0;
591
592 dt_root_size_cells = OF_ROOT_NODE_SIZE_CELLS_DEFAULT;
593 dt_root_addr_cells = OF_ROOT_NODE_ADDR_CELLS_DEFAULT;
594
595 prop = of_get_flat_dt_prop(node, "#size-cells", NULL);
596 if (prop)
597 dt_root_size_cells = be32_to_cpup(prop);
598 pr_debug("dt_root_size_cells = %x\n", dt_root_size_cells);
599
600 prop = of_get_flat_dt_prop(node, "#address-cells", NULL);
601 if (prop)
602 dt_root_addr_cells = be32_to_cpup(prop);
603 pr_debug("dt_root_addr_cells = %x\n", dt_root_addr_cells);
604
605 /* break now */
606 return 1;
607}
608
609u64 __init dt_mem_next_cell(int s, __be32 **cellp)
610{
611 __be32 *p = *cellp;
612
613 *cellp = p + s;
614 return of_read_number(p, s);
615}
616
617/**
618 * early_init_dt_scan_memory - Look for an parse memory nodes
619 */
620int __init early_init_dt_scan_memory(unsigned long node, const char *uname,
621 int depth, void *data)
622{
623 char *type = of_get_flat_dt_prop(node, "device_type", NULL);
624 __be32 *reg, *endp;
625 unsigned long l;
626
627 /* We are scanning "memory" nodes only */
628 if (type == NULL) {
629 /*
630 * The longtrail doesn't have a device_type on the
631 * /memory node, so look for the node called /memory@0.
632 */
633 if (depth != 1 || strcmp(uname, "memory@0") != 0)
634 return 0;
635 } else if (strcmp(type, "memory") != 0)
636 return 0;
637
638 reg = of_get_flat_dt_prop(node, "linux,usable-memory", &l);
639 if (reg == NULL)
640 reg = of_get_flat_dt_prop(node, "reg", &l);
641 if (reg == NULL)
642 return 0;
643
644 endp = reg + (l / sizeof(__be32));
645
646 pr_debug("memory scan node %s, reg size %ld, data: %x %x %x %x,\n",
647 uname, l, reg[0], reg[1], reg[2], reg[3]);
648
649 while ((endp - reg) >= (dt_root_addr_cells + dt_root_size_cells)) {
650 u64 base, size;
651
652 base = dt_mem_next_cell(dt_root_addr_cells, ®);
653 size = dt_mem_next_cell(dt_root_size_cells, ®);
654
655 if (size == 0)
656 continue;
657 pr_debug(" - %llx , %llx\n", (unsigned long long)base,
658 (unsigned long long)size);
659
660 early_init_dt_add_memory_arch(base, size);
661 }
662
663 return 0;
664}
665
666int __init early_init_dt_scan_chosen(unsigned long node, const char *uname,
667 int depth, void *data)
668{
669 unsigned long l;
670 char *p;
671
672 pr_debug("search \"chosen\", depth: %d, uname: %s\n", depth, uname);
673
674 if (depth != 1 || !data ||
675 (strcmp(uname, "chosen") != 0 && strcmp(uname, "chosen@0") != 0))
676 return 0;
677
678 early_init_dt_check_for_initrd(node);
679
680 /* Retrieve command line */
681 p = of_get_flat_dt_prop(node, "bootargs", &l);
682 if (p != NULL && l > 0)
683 strlcpy(data, p, min((int)l, COMMAND_LINE_SIZE));
684
685 /*
686 * CONFIG_CMDLINE is meant to be a default in case nothing else
687 * managed to set the command line, unless CONFIG_CMDLINE_FORCE
688 * is set in which case we override whatever was found earlier.
689 */
690#ifdef CONFIG_CMDLINE
691#ifndef CONFIG_CMDLINE_FORCE
692 if (!((char *)data)[0])
693#endif
694 strlcpy(data, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
695#endif /* CONFIG_CMDLINE */
696
697 pr_debug("Command line is: %s\n", (char*)data);
698
699 /* break now */
700 return 1;
701}
702
703/**
704 * unflatten_device_tree - create tree of device_nodes from flat blob
705 *
706 * unflattens the device-tree passed by the firmware, creating the
707 * tree of struct device_node. It also fills the "name" and "type"
708 * pointers of the nodes so the normal device-tree walking functions
709 * can be used.
710 */
711void __init unflatten_device_tree(void)
712{
713 __unflatten_device_tree(initial_boot_params, &allnodes,
714 early_init_dt_alloc_memory_arch);
715
716 /* Get pointer to "/chosen" and "/aliasas" nodes for use everywhere */
717 of_alias_scan(early_init_dt_alloc_memory_arch);
718}
719
720#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/crc32.h>
13#include <linux/kernel.h>
14#include <linux/initrd.h>
15#include <linux/memblock.h>
16#include <linux/mutex.h>
17#include <linux/of.h>
18#include <linux/of_fdt.h>
19#include <linux/of_reserved_mem.h>
20#include <linux/sizes.h>
21#include <linux/string.h>
22#include <linux/errno.h>
23#include <linux/slab.h>
24#include <linux/libfdt.h>
25#include <linux/debugfs.h>
26#include <linux/serial_core.h>
27#include <linux/sysfs.h>
28
29#include <asm/setup.h> /* for COMMAND_LINE_SIZE */
30#include <asm/page.h>
31
32/*
33 * of_fdt_limit_memory - limit the number of regions in the /memory node
34 * @limit: maximum entries
35 *
36 * Adjust the flattened device tree to have at most 'limit' number of
37 * memory entries in the /memory node. This function may be called
38 * any time after initial_boot_param is set.
39 */
40void of_fdt_limit_memory(int limit)
41{
42 int memory;
43 int len;
44 const void *val;
45 int nr_address_cells = OF_ROOT_NODE_ADDR_CELLS_DEFAULT;
46 int nr_size_cells = OF_ROOT_NODE_SIZE_CELLS_DEFAULT;
47 const uint32_t *addr_prop;
48 const uint32_t *size_prop;
49 int root_offset;
50 int cell_size;
51
52 root_offset = fdt_path_offset(initial_boot_params, "/");
53 if (root_offset < 0)
54 return;
55
56 addr_prop = fdt_getprop(initial_boot_params, root_offset,
57 "#address-cells", NULL);
58 if (addr_prop)
59 nr_address_cells = fdt32_to_cpu(*addr_prop);
60
61 size_prop = fdt_getprop(initial_boot_params, root_offset,
62 "#size-cells", NULL);
63 if (size_prop)
64 nr_size_cells = fdt32_to_cpu(*size_prop);
65
66 cell_size = sizeof(uint32_t)*(nr_address_cells + nr_size_cells);
67
68 memory = fdt_path_offset(initial_boot_params, "/memory");
69 if (memory > 0) {
70 val = fdt_getprop(initial_boot_params, memory, "reg", &len);
71 if (len > limit*cell_size) {
72 len = limit*cell_size;
73 pr_debug("Limiting number of entries to %d\n", limit);
74 fdt_setprop(initial_boot_params, memory, "reg", val,
75 len);
76 }
77 }
78}
79
80/**
81 * of_fdt_is_compatible - Return true if given node from the given blob has
82 * compat in its compatible list
83 * @blob: A device tree blob
84 * @node: node to test
85 * @compat: compatible string to compare with compatible list.
86 *
87 * On match, returns a non-zero value with smaller values returned for more
88 * specific compatible values.
89 */
90int of_fdt_is_compatible(const void *blob,
91 unsigned long node, const char *compat)
92{
93 const char *cp;
94 int cplen;
95 unsigned long l, score = 0;
96
97 cp = fdt_getprop(blob, node, "compatible", &cplen);
98 if (cp == NULL)
99 return 0;
100 while (cplen > 0) {
101 score++;
102 if (of_compat_cmp(cp, compat, strlen(compat)) == 0)
103 return score;
104 l = strlen(cp) + 1;
105 cp += l;
106 cplen -= l;
107 }
108
109 return 0;
110}
111
112/**
113 * of_fdt_is_big_endian - Return true if given node needs BE MMIO accesses
114 * @blob: A device tree blob
115 * @node: node to test
116 *
117 * Returns true if the node has a "big-endian" property, or if the kernel
118 * was compiled for BE *and* the node has a "native-endian" property.
119 * Returns false otherwise.
120 */
121bool of_fdt_is_big_endian(const void *blob, unsigned long node)
122{
123 if (fdt_getprop(blob, node, "big-endian", NULL))
124 return true;
125 if (IS_ENABLED(CONFIG_CPU_BIG_ENDIAN) &&
126 fdt_getprop(blob, node, "native-endian", NULL))
127 return true;
128 return false;
129}
130
131/**
132 * of_fdt_match - Return true if node matches a list of compatible values
133 */
134int of_fdt_match(const void *blob, unsigned long node,
135 const char *const *compat)
136{
137 unsigned int tmp, score = 0;
138
139 if (!compat)
140 return 0;
141
142 while (*compat) {
143 tmp = of_fdt_is_compatible(blob, node, *compat);
144 if (tmp && (score == 0 || (tmp < score)))
145 score = tmp;
146 compat++;
147 }
148
149 return score;
150}
151
152static void *unflatten_dt_alloc(void **mem, unsigned long size,
153 unsigned long align)
154{
155 void *res;
156
157 *mem = PTR_ALIGN(*mem, align);
158 res = *mem;
159 *mem += size;
160
161 return res;
162}
163
164/**
165 * unflatten_dt_node - Alloc and populate a device_node from the flat tree
166 * @blob: The parent device tree blob
167 * @mem: Memory chunk to use for allocating device nodes and properties
168 * @poffset: pointer to node in flat tree
169 * @dad: Parent struct device_node
170 * @nodepp: The device_node tree created by the call
171 * @fpsize: Size of the node path up at the current depth.
172 * @dryrun: If true, do not allocate device nodes but still calculate needed
173 * memory size
174 */
175static void * unflatten_dt_node(const void *blob,
176 void *mem,
177 int *poffset,
178 struct device_node *dad,
179 struct device_node **nodepp,
180 unsigned long fpsize,
181 bool dryrun)
182{
183 const __be32 *p;
184 struct device_node *np;
185 struct property *pp, **prev_pp = NULL;
186 const char *pathp;
187 unsigned int l, allocl;
188 static int depth;
189 int old_depth;
190 int offset;
191 int has_name = 0;
192 int new_format = 0;
193
194 pathp = fdt_get_name(blob, *poffset, &l);
195 if (!pathp)
196 return mem;
197
198 allocl = ++l;
199
200 /* version 0x10 has a more compact unit name here instead of the full
201 * path. we accumulate the full path size using "fpsize", we'll rebuild
202 * it later. We detect this because the first character of the name is
203 * not '/'.
204 */
205 if ((*pathp) != '/') {
206 new_format = 1;
207 if (fpsize == 0) {
208 /* root node: special case. fpsize accounts for path
209 * plus terminating zero. root node only has '/', so
210 * fpsize should be 2, but we want to avoid the first
211 * level nodes to have two '/' so we use fpsize 1 here
212 */
213 fpsize = 1;
214 allocl = 2;
215 l = 1;
216 pathp = "";
217 } else {
218 /* account for '/' and path size minus terminal 0
219 * already in 'l'
220 */
221 fpsize += l;
222 allocl = fpsize;
223 }
224 }
225
226 np = unflatten_dt_alloc(&mem, sizeof(struct device_node) + allocl,
227 __alignof__(struct device_node));
228 if (!dryrun) {
229 char *fn;
230 of_node_init(np);
231 np->full_name = fn = ((char *)np) + sizeof(*np);
232 if (new_format) {
233 /* rebuild full path for new format */
234 if (dad && dad->parent) {
235 strcpy(fn, dad->full_name);
236#ifdef DEBUG
237 if ((strlen(fn) + l + 1) != allocl) {
238 pr_debug("%s: p: %d, l: %d, a: %d\n",
239 pathp, (int)strlen(fn),
240 l, allocl);
241 }
242#endif
243 fn += strlen(fn);
244 }
245 *(fn++) = '/';
246 }
247 memcpy(fn, pathp, l);
248
249 prev_pp = &np->properties;
250 if (dad != NULL) {
251 np->parent = dad;
252 np->sibling = dad->child;
253 dad->child = np;
254 }
255 }
256 /* process properties */
257 for (offset = fdt_first_property_offset(blob, *poffset);
258 (offset >= 0);
259 (offset = fdt_next_property_offset(blob, offset))) {
260 const char *pname;
261 u32 sz;
262
263 if (!(p = fdt_getprop_by_offset(blob, offset, &pname, &sz))) {
264 offset = -FDT_ERR_INTERNAL;
265 break;
266 }
267
268 if (pname == NULL) {
269 pr_info("Can't find property name in list !\n");
270 break;
271 }
272 if (strcmp(pname, "name") == 0)
273 has_name = 1;
274 pp = unflatten_dt_alloc(&mem, sizeof(struct property),
275 __alignof__(struct property));
276 if (!dryrun) {
277 /* We accept flattened tree phandles either in
278 * ePAPR-style "phandle" properties, or the
279 * legacy "linux,phandle" properties. If both
280 * appear and have different values, things
281 * will get weird. Don't do that. */
282 if ((strcmp(pname, "phandle") == 0) ||
283 (strcmp(pname, "linux,phandle") == 0)) {
284 if (np->phandle == 0)
285 np->phandle = be32_to_cpup(p);
286 }
287 /* And we process the "ibm,phandle" property
288 * used in pSeries dynamic device tree
289 * stuff */
290 if (strcmp(pname, "ibm,phandle") == 0)
291 np->phandle = be32_to_cpup(p);
292 pp->name = (char *)pname;
293 pp->length = sz;
294 pp->value = (__be32 *)p;
295 *prev_pp = pp;
296 prev_pp = &pp->next;
297 }
298 }
299 /* with version 0x10 we may not have the name property, recreate
300 * it here from the unit name if absent
301 */
302 if (!has_name) {
303 const char *p1 = pathp, *ps = pathp, *pa = NULL;
304 int sz;
305
306 while (*p1) {
307 if ((*p1) == '@')
308 pa = p1;
309 if ((*p1) == '/')
310 ps = p1 + 1;
311 p1++;
312 }
313 if (pa < ps)
314 pa = p1;
315 sz = (pa - ps) + 1;
316 pp = unflatten_dt_alloc(&mem, sizeof(struct property) + sz,
317 __alignof__(struct property));
318 if (!dryrun) {
319 pp->name = "name";
320 pp->length = sz;
321 pp->value = pp + 1;
322 *prev_pp = pp;
323 prev_pp = &pp->next;
324 memcpy(pp->value, ps, sz - 1);
325 ((char *)pp->value)[sz - 1] = 0;
326 pr_debug("fixed up name for %s -> %s\n", pathp,
327 (char *)pp->value);
328 }
329 }
330 if (!dryrun) {
331 *prev_pp = NULL;
332 np->name = of_get_property(np, "name", NULL);
333 np->type = of_get_property(np, "device_type", NULL);
334
335 if (!np->name)
336 np->name = "<NULL>";
337 if (!np->type)
338 np->type = "<NULL>";
339 }
340
341 old_depth = depth;
342 *poffset = fdt_next_node(blob, *poffset, &depth);
343 if (depth < 0)
344 depth = 0;
345 while (*poffset > 0 && depth > old_depth)
346 mem = unflatten_dt_node(blob, mem, poffset, np, NULL,
347 fpsize, dryrun);
348
349 if (*poffset < 0 && *poffset != -FDT_ERR_NOTFOUND)
350 pr_err("unflatten: error %d processing FDT\n", *poffset);
351
352 /*
353 * Reverse the child list. Some drivers assumes node order matches .dts
354 * node order
355 */
356 if (!dryrun && np->child) {
357 struct device_node *child = np->child;
358 np->child = NULL;
359 while (child) {
360 struct device_node *next = child->sibling;
361 child->sibling = np->child;
362 np->child = child;
363 child = next;
364 }
365 }
366
367 if (nodepp)
368 *nodepp = np;
369
370 return mem;
371}
372
373/**
374 * __unflatten_device_tree - create tree of device_nodes from flat blob
375 *
376 * unflattens a device-tree, creating the
377 * tree of struct device_node. It also fills the "name" and "type"
378 * pointers of the nodes so the normal device-tree walking functions
379 * can be used.
380 * @blob: The blob to expand
381 * @mynodes: The device_node tree created by the call
382 * @dt_alloc: An allocator that provides a virtual address to memory
383 * for the resulting tree
384 */
385static void __unflatten_device_tree(const void *blob,
386 struct device_node **mynodes,
387 void * (*dt_alloc)(u64 size, u64 align))
388{
389 unsigned long size;
390 int start;
391 void *mem;
392
393 pr_debug(" -> unflatten_device_tree()\n");
394
395 if (!blob) {
396 pr_debug("No device tree pointer\n");
397 return;
398 }
399
400 pr_debug("Unflattening device tree:\n");
401 pr_debug("magic: %08x\n", fdt_magic(blob));
402 pr_debug("size: %08x\n", fdt_totalsize(blob));
403 pr_debug("version: %08x\n", fdt_version(blob));
404
405 if (fdt_check_header(blob)) {
406 pr_err("Invalid device tree blob header\n");
407 return;
408 }
409
410 /* First pass, scan for size */
411 start = 0;
412 size = (unsigned long)unflatten_dt_node(blob, NULL, &start, NULL, NULL, 0, true);
413 size = ALIGN(size, 4);
414
415 pr_debug(" size is %lx, allocating...\n", size);
416
417 /* Allocate memory for the expanded device tree */
418 mem = dt_alloc(size + 4, __alignof__(struct device_node));
419 memset(mem, 0, size);
420
421 *(__be32 *)(mem + size) = cpu_to_be32(0xdeadbeef);
422
423 pr_debug(" unflattening %p...\n", mem);
424
425 /* Second pass, do actual unflattening */
426 start = 0;
427 unflatten_dt_node(blob, mem, &start, NULL, mynodes, 0, false);
428 if (be32_to_cpup(mem + size) != 0xdeadbeef)
429 pr_warning("End of tree marker overwritten: %08x\n",
430 be32_to_cpup(mem + size));
431
432 pr_debug(" <- unflatten_device_tree()\n");
433}
434
435static void *kernel_tree_alloc(u64 size, u64 align)
436{
437 return kzalloc(size, GFP_KERNEL);
438}
439
440static DEFINE_MUTEX(of_fdt_unflatten_mutex);
441
442/**
443 * of_fdt_unflatten_tree - create tree of device_nodes from flat blob
444 *
445 * unflattens the device-tree passed by the firmware, creating the
446 * tree of struct device_node. It also fills the "name" and "type"
447 * pointers of the nodes so the normal device-tree walking functions
448 * can be used.
449 */
450void of_fdt_unflatten_tree(const unsigned long *blob,
451 struct device_node **mynodes)
452{
453 mutex_lock(&of_fdt_unflatten_mutex);
454 __unflatten_device_tree(blob, mynodes, &kernel_tree_alloc);
455 mutex_unlock(&of_fdt_unflatten_mutex);
456}
457EXPORT_SYMBOL_GPL(of_fdt_unflatten_tree);
458
459/* Everything below here references initial_boot_params directly. */
460int __initdata dt_root_addr_cells;
461int __initdata dt_root_size_cells;
462
463void *initial_boot_params;
464
465#ifdef CONFIG_OF_EARLY_FLATTREE
466
467static u32 of_fdt_crc32;
468
469/**
470 * res_mem_reserve_reg() - reserve all memory described in 'reg' property
471 */
472static int __init __reserved_mem_reserve_reg(unsigned long node,
473 const char *uname)
474{
475 int t_len = (dt_root_addr_cells + dt_root_size_cells) * sizeof(__be32);
476 phys_addr_t base, size;
477 int len;
478 const __be32 *prop;
479 int nomap, first = 1;
480
481 prop = of_get_flat_dt_prop(node, "reg", &len);
482 if (!prop)
483 return -ENOENT;
484
485 if (len && len % t_len != 0) {
486 pr_err("Reserved memory: invalid reg property in '%s', skipping node.\n",
487 uname);
488 return -EINVAL;
489 }
490
491 nomap = of_get_flat_dt_prop(node, "no-map", NULL) != NULL;
492
493 while (len >= t_len) {
494 base = dt_mem_next_cell(dt_root_addr_cells, &prop);
495 size = dt_mem_next_cell(dt_root_size_cells, &prop);
496
497 if (size &&
498 early_init_dt_reserve_memory_arch(base, size, nomap) == 0)
499 pr_debug("Reserved memory: reserved region for node '%s': base %pa, size %ld MiB\n",
500 uname, &base, (unsigned long)size / SZ_1M);
501 else
502 pr_info("Reserved memory: failed to reserve memory for node '%s': base %pa, size %ld MiB\n",
503 uname, &base, (unsigned long)size / SZ_1M);
504
505 len -= t_len;
506 if (first) {
507 fdt_reserved_mem_save_node(node, uname, base, size);
508 first = 0;
509 }
510 }
511 return 0;
512}
513
514/**
515 * __reserved_mem_check_root() - check if #size-cells, #address-cells provided
516 * in /reserved-memory matches the values supported by the current implementation,
517 * also check if ranges property has been provided
518 */
519static int __init __reserved_mem_check_root(unsigned long node)
520{
521 const __be32 *prop;
522
523 prop = of_get_flat_dt_prop(node, "#size-cells", NULL);
524 if (!prop || be32_to_cpup(prop) != dt_root_size_cells)
525 return -EINVAL;
526
527 prop = of_get_flat_dt_prop(node, "#address-cells", NULL);
528 if (!prop || be32_to_cpup(prop) != dt_root_addr_cells)
529 return -EINVAL;
530
531 prop = of_get_flat_dt_prop(node, "ranges", NULL);
532 if (!prop)
533 return -EINVAL;
534 return 0;
535}
536
537/**
538 * fdt_scan_reserved_mem() - scan a single FDT node for reserved memory
539 */
540static int __init __fdt_scan_reserved_mem(unsigned long node, const char *uname,
541 int depth, void *data)
542{
543 static int found;
544 const char *status;
545 int err;
546
547 if (!found && depth == 1 && strcmp(uname, "reserved-memory") == 0) {
548 if (__reserved_mem_check_root(node) != 0) {
549 pr_err("Reserved memory: unsupported node format, ignoring\n");
550 /* break scan */
551 return 1;
552 }
553 found = 1;
554 /* scan next node */
555 return 0;
556 } else if (!found) {
557 /* scan next node */
558 return 0;
559 } else if (found && depth < 2) {
560 /* scanning of /reserved-memory has been finished */
561 return 1;
562 }
563
564 status = of_get_flat_dt_prop(node, "status", NULL);
565 if (status && strcmp(status, "okay") != 0 && strcmp(status, "ok") != 0)
566 return 0;
567
568 err = __reserved_mem_reserve_reg(node, uname);
569 if (err == -ENOENT && of_get_flat_dt_prop(node, "size", NULL))
570 fdt_reserved_mem_save_node(node, uname, 0, 0);
571
572 /* scan next node */
573 return 0;
574}
575
576/**
577 * early_init_fdt_scan_reserved_mem() - create reserved memory regions
578 *
579 * This function grabs memory from early allocator for device exclusive use
580 * defined in device tree structures. It should be called by arch specific code
581 * once the early allocator (i.e. memblock) has been fully activated.
582 */
583void __init early_init_fdt_scan_reserved_mem(void)
584{
585 int n;
586 u64 base, size;
587
588 if (!initial_boot_params)
589 return;
590
591 /* Process header /memreserve/ fields */
592 for (n = 0; ; n++) {
593 fdt_get_mem_rsv(initial_boot_params, n, &base, &size);
594 if (!size)
595 break;
596 early_init_dt_reserve_memory_arch(base, size, 0);
597 }
598
599 of_scan_flat_dt(__fdt_scan_reserved_mem, NULL);
600 fdt_init_reserved_mem();
601}
602
603/**
604 * early_init_fdt_reserve_self() - reserve the memory used by the FDT blob
605 */
606void __init early_init_fdt_reserve_self(void)
607{
608 if (!initial_boot_params)
609 return;
610
611 /* Reserve the dtb region */
612 early_init_dt_reserve_memory_arch(__pa(initial_boot_params),
613 fdt_totalsize(initial_boot_params),
614 0);
615}
616
617/**
618 * of_scan_flat_dt - scan flattened tree blob and call callback on each.
619 * @it: callback function
620 * @data: context data pointer
621 *
622 * This function is used to scan the flattened device-tree, it is
623 * used to extract the memory information at boot before we can
624 * unflatten the tree
625 */
626int __init of_scan_flat_dt(int (*it)(unsigned long node,
627 const char *uname, int depth,
628 void *data),
629 void *data)
630{
631 const void *blob = initial_boot_params;
632 const char *pathp;
633 int offset, rc = 0, depth = -1;
634
635 for (offset = fdt_next_node(blob, -1, &depth);
636 offset >= 0 && depth >= 0 && !rc;
637 offset = fdt_next_node(blob, offset, &depth)) {
638
639 pathp = fdt_get_name(blob, offset, NULL);
640 if (*pathp == '/')
641 pathp = kbasename(pathp);
642 rc = it(offset, pathp, depth, data);
643 }
644 return rc;
645}
646
647/**
648 * of_get_flat_dt_root - find the root node in the flat blob
649 */
650unsigned long __init of_get_flat_dt_root(void)
651{
652 return 0;
653}
654
655/**
656 * of_get_flat_dt_size - Return the total size of the FDT
657 */
658int __init of_get_flat_dt_size(void)
659{
660 return fdt_totalsize(initial_boot_params);
661}
662
663/**
664 * of_get_flat_dt_prop - Given a node in the flat blob, return the property ptr
665 *
666 * This function can be used within scan_flattened_dt callback to get
667 * access to properties
668 */
669const void *__init of_get_flat_dt_prop(unsigned long node, const char *name,
670 int *size)
671{
672 return fdt_getprop(initial_boot_params, node, name, size);
673}
674
675/**
676 * of_flat_dt_is_compatible - Return true if given node has compat in compatible list
677 * @node: node to test
678 * @compat: compatible string to compare with compatible list.
679 */
680int __init of_flat_dt_is_compatible(unsigned long node, const char *compat)
681{
682 return of_fdt_is_compatible(initial_boot_params, node, compat);
683}
684
685/**
686 * of_flat_dt_match - Return true if node matches a list of compatible values
687 */
688int __init of_flat_dt_match(unsigned long node, const char *const *compat)
689{
690 return of_fdt_match(initial_boot_params, node, compat);
691}
692
693struct fdt_scan_status {
694 const char *name;
695 int namelen;
696 int depth;
697 int found;
698 int (*iterator)(unsigned long node, const char *uname, int depth, void *data);
699 void *data;
700};
701
702const char * __init of_flat_dt_get_machine_name(void)
703{
704 const char *name;
705 unsigned long dt_root = of_get_flat_dt_root();
706
707 name = of_get_flat_dt_prop(dt_root, "model", NULL);
708 if (!name)
709 name = of_get_flat_dt_prop(dt_root, "compatible", NULL);
710 return name;
711}
712
713/**
714 * of_flat_dt_match_machine - Iterate match tables to find matching machine.
715 *
716 * @default_match: A machine specific ptr to return in case of no match.
717 * @get_next_compat: callback function to return next compatible match table.
718 *
719 * Iterate through machine match tables to find the best match for the machine
720 * compatible string in the FDT.
721 */
722const void * __init of_flat_dt_match_machine(const void *default_match,
723 const void * (*get_next_compat)(const char * const**))
724{
725 const void *data = NULL;
726 const void *best_data = default_match;
727 const char *const *compat;
728 unsigned long dt_root;
729 unsigned int best_score = ~1, score = 0;
730
731 dt_root = of_get_flat_dt_root();
732 while ((data = get_next_compat(&compat))) {
733 score = of_flat_dt_match(dt_root, compat);
734 if (score > 0 && score < best_score) {
735 best_data = data;
736 best_score = score;
737 }
738 }
739 if (!best_data) {
740 const char *prop;
741 int size;
742
743 pr_err("\n unrecognized device tree list:\n[ ");
744
745 prop = of_get_flat_dt_prop(dt_root, "compatible", &size);
746 if (prop) {
747 while (size > 0) {
748 printk("'%s' ", prop);
749 size -= strlen(prop) + 1;
750 prop += strlen(prop) + 1;
751 }
752 }
753 printk("]\n\n");
754 return NULL;
755 }
756
757 pr_info("Machine model: %s\n", of_flat_dt_get_machine_name());
758
759 return best_data;
760}
761
762#ifdef CONFIG_BLK_DEV_INITRD
763#ifndef __early_init_dt_declare_initrd
764static void __early_init_dt_declare_initrd(unsigned long start,
765 unsigned long end)
766{
767 initrd_start = (unsigned long)__va(start);
768 initrd_end = (unsigned long)__va(end);
769 initrd_below_start_ok = 1;
770}
771#endif
772
773/**
774 * early_init_dt_check_for_initrd - Decode initrd location from flat tree
775 * @node: reference to node containing initrd location ('chosen')
776 */
777static void __init early_init_dt_check_for_initrd(unsigned long node)
778{
779 u64 start, end;
780 int len;
781 const __be32 *prop;
782
783 pr_debug("Looking for initrd properties... ");
784
785 prop = of_get_flat_dt_prop(node, "linux,initrd-start", &len);
786 if (!prop)
787 return;
788 start = of_read_number(prop, len/4);
789
790 prop = of_get_flat_dt_prop(node, "linux,initrd-end", &len);
791 if (!prop)
792 return;
793 end = of_read_number(prop, len/4);
794
795 __early_init_dt_declare_initrd(start, end);
796
797 pr_debug("initrd_start=0x%llx initrd_end=0x%llx\n",
798 (unsigned long long)start, (unsigned long long)end);
799}
800#else
801static inline void early_init_dt_check_for_initrd(unsigned long node)
802{
803}
804#endif /* CONFIG_BLK_DEV_INITRD */
805
806#ifdef CONFIG_SERIAL_EARLYCON
807
808static int __init early_init_dt_scan_chosen_serial(void)
809{
810 int offset;
811 const char *p, *q, *options = NULL;
812 int l;
813 const struct earlycon_id *match;
814 const void *fdt = initial_boot_params;
815
816 offset = fdt_path_offset(fdt, "/chosen");
817 if (offset < 0)
818 offset = fdt_path_offset(fdt, "/chosen@0");
819 if (offset < 0)
820 return -ENOENT;
821
822 p = fdt_getprop(fdt, offset, "stdout-path", &l);
823 if (!p)
824 p = fdt_getprop(fdt, offset, "linux,stdout-path", &l);
825 if (!p || !l)
826 return -ENOENT;
827
828 q = strchrnul(p, ':');
829 if (*q != '\0')
830 options = q + 1;
831 l = q - p;
832
833 /* Get the node specified by stdout-path */
834 offset = fdt_path_offset_namelen(fdt, p, l);
835 if (offset < 0) {
836 pr_warn("earlycon: stdout-path %.*s not found\n", l, p);
837 return 0;
838 }
839
840 for (match = __earlycon_table; match < __earlycon_table_end; match++) {
841 if (!match->compatible[0])
842 continue;
843
844 if (fdt_node_check_compatible(fdt, offset, match->compatible))
845 continue;
846
847 of_setup_earlycon(match, offset, options);
848 return 0;
849 }
850 return -ENODEV;
851}
852
853static int __init setup_of_earlycon(char *buf)
854{
855 if (buf)
856 return 0;
857
858 return early_init_dt_scan_chosen_serial();
859}
860early_param("earlycon", setup_of_earlycon);
861#endif
862
863/**
864 * early_init_dt_scan_root - fetch the top level address and size cells
865 */
866int __init early_init_dt_scan_root(unsigned long node, const char *uname,
867 int depth, void *data)
868{
869 const __be32 *prop;
870
871 if (depth != 0)
872 return 0;
873
874 dt_root_size_cells = OF_ROOT_NODE_SIZE_CELLS_DEFAULT;
875 dt_root_addr_cells = OF_ROOT_NODE_ADDR_CELLS_DEFAULT;
876
877 prop = of_get_flat_dt_prop(node, "#size-cells", NULL);
878 if (prop)
879 dt_root_size_cells = be32_to_cpup(prop);
880 pr_debug("dt_root_size_cells = %x\n", dt_root_size_cells);
881
882 prop = of_get_flat_dt_prop(node, "#address-cells", NULL);
883 if (prop)
884 dt_root_addr_cells = be32_to_cpup(prop);
885 pr_debug("dt_root_addr_cells = %x\n", dt_root_addr_cells);
886
887 /* break now */
888 return 1;
889}
890
891u64 __init dt_mem_next_cell(int s, const __be32 **cellp)
892{
893 const __be32 *p = *cellp;
894
895 *cellp = p + s;
896 return of_read_number(p, s);
897}
898
899/**
900 * early_init_dt_scan_memory - Look for an parse memory nodes
901 */
902int __init early_init_dt_scan_memory(unsigned long node, const char *uname,
903 int depth, void *data)
904{
905 const char *type = of_get_flat_dt_prop(node, "device_type", NULL);
906 const __be32 *reg, *endp;
907 int l;
908
909 /* We are scanning "memory" nodes only */
910 if (type == NULL) {
911 /*
912 * The longtrail doesn't have a device_type on the
913 * /memory node, so look for the node called /memory@0.
914 */
915 if (!IS_ENABLED(CONFIG_PPC32) || depth != 1 || strcmp(uname, "memory@0") != 0)
916 return 0;
917 } else if (strcmp(type, "memory") != 0)
918 return 0;
919
920 reg = of_get_flat_dt_prop(node, "linux,usable-memory", &l);
921 if (reg == NULL)
922 reg = of_get_flat_dt_prop(node, "reg", &l);
923 if (reg == NULL)
924 return 0;
925
926 endp = reg + (l / sizeof(__be32));
927
928 pr_debug("memory scan node %s, reg size %d,\n", uname, l);
929
930 while ((endp - reg) >= (dt_root_addr_cells + dt_root_size_cells)) {
931 u64 base, size;
932
933 base = dt_mem_next_cell(dt_root_addr_cells, ®);
934 size = dt_mem_next_cell(dt_root_size_cells, ®);
935
936 if (size == 0)
937 continue;
938 pr_debug(" - %llx , %llx\n", (unsigned long long)base,
939 (unsigned long long)size);
940
941 early_init_dt_add_memory_arch(base, size);
942 }
943
944 return 0;
945}
946
947int __init early_init_dt_scan_chosen(unsigned long node, const char *uname,
948 int depth, void *data)
949{
950 int l;
951 const char *p;
952
953 pr_debug("search \"chosen\", depth: %d, uname: %s\n", depth, uname);
954
955 if (depth != 1 || !data ||
956 (strcmp(uname, "chosen") != 0 && strcmp(uname, "chosen@0") != 0))
957 return 0;
958
959 early_init_dt_check_for_initrd(node);
960
961 /* Retrieve command line */
962 p = of_get_flat_dt_prop(node, "bootargs", &l);
963 if (p != NULL && l > 0)
964 strlcpy(data, p, min((int)l, COMMAND_LINE_SIZE));
965
966 /*
967 * CONFIG_CMDLINE is meant to be a default in case nothing else
968 * managed to set the command line, unless CONFIG_CMDLINE_FORCE
969 * is set in which case we override whatever was found earlier.
970 */
971#ifdef CONFIG_CMDLINE
972#ifndef CONFIG_CMDLINE_FORCE
973 if (!((char *)data)[0])
974#endif
975 strlcpy(data, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
976#endif /* CONFIG_CMDLINE */
977
978 pr_debug("Command line is: %s\n", (char*)data);
979
980 /* break now */
981 return 1;
982}
983
984#ifdef CONFIG_HAVE_MEMBLOCK
985#ifndef MIN_MEMBLOCK_ADDR
986#define MIN_MEMBLOCK_ADDR __pa(PAGE_OFFSET)
987#endif
988#ifndef MAX_MEMBLOCK_ADDR
989#define MAX_MEMBLOCK_ADDR ((phys_addr_t)~0)
990#endif
991
992void __init __weak early_init_dt_add_memory_arch(u64 base, u64 size)
993{
994 const u64 phys_offset = MIN_MEMBLOCK_ADDR;
995
996 if (!PAGE_ALIGNED(base)) {
997 if (size < PAGE_SIZE - (base & ~PAGE_MASK)) {
998 pr_warn("Ignoring memory block 0x%llx - 0x%llx\n",
999 base, base + size);
1000 return;
1001 }
1002 size -= PAGE_SIZE - (base & ~PAGE_MASK);
1003 base = PAGE_ALIGN(base);
1004 }
1005 size &= PAGE_MASK;
1006
1007 if (base > MAX_MEMBLOCK_ADDR) {
1008 pr_warning("Ignoring memory block 0x%llx - 0x%llx\n",
1009 base, base + size);
1010 return;
1011 }
1012
1013 if (base + size - 1 > MAX_MEMBLOCK_ADDR) {
1014 pr_warning("Ignoring memory range 0x%llx - 0x%llx\n",
1015 ((u64)MAX_MEMBLOCK_ADDR) + 1, base + size);
1016 size = MAX_MEMBLOCK_ADDR - base + 1;
1017 }
1018
1019 if (base + size < phys_offset) {
1020 pr_warning("Ignoring memory block 0x%llx - 0x%llx\n",
1021 base, base + size);
1022 return;
1023 }
1024 if (base < phys_offset) {
1025 pr_warning("Ignoring memory range 0x%llx - 0x%llx\n",
1026 base, phys_offset);
1027 size -= phys_offset - base;
1028 base = phys_offset;
1029 }
1030 memblock_add(base, size);
1031}
1032
1033int __init __weak early_init_dt_reserve_memory_arch(phys_addr_t base,
1034 phys_addr_t size, bool nomap)
1035{
1036 if (nomap)
1037 return memblock_remove(base, size);
1038 return memblock_reserve(base, size);
1039}
1040
1041/*
1042 * called from unflatten_device_tree() to bootstrap devicetree itself
1043 * Architectures can override this definition if memblock isn't used
1044 */
1045void * __init __weak early_init_dt_alloc_memory_arch(u64 size, u64 align)
1046{
1047 return __va(memblock_alloc(size, align));
1048}
1049#else
1050void __init __weak early_init_dt_add_memory_arch(u64 base, u64 size)
1051{
1052 WARN_ON(1);
1053}
1054
1055int __init __weak early_init_dt_reserve_memory_arch(phys_addr_t base,
1056 phys_addr_t size, bool nomap)
1057{
1058 pr_err("Reserved memory not supported, ignoring range %pa - %pa%s\n",
1059 &base, &size, nomap ? " (nomap)" : "");
1060 return -ENOSYS;
1061}
1062
1063void * __init __weak early_init_dt_alloc_memory_arch(u64 size, u64 align)
1064{
1065 WARN_ON(1);
1066 return NULL;
1067}
1068#endif
1069
1070bool __init early_init_dt_verify(void *params)
1071{
1072 if (!params)
1073 return false;
1074
1075 /* check device tree validity */
1076 if (fdt_check_header(params))
1077 return false;
1078
1079 /* Setup flat device-tree pointer */
1080 initial_boot_params = params;
1081 of_fdt_crc32 = crc32_be(~0, initial_boot_params,
1082 fdt_totalsize(initial_boot_params));
1083 return true;
1084}
1085
1086
1087void __init early_init_dt_scan_nodes(void)
1088{
1089 /* Retrieve various information from the /chosen node */
1090 of_scan_flat_dt(early_init_dt_scan_chosen, boot_command_line);
1091
1092 /* Initialize {size,address}-cells info */
1093 of_scan_flat_dt(early_init_dt_scan_root, NULL);
1094
1095 /* Setup memory, calling early_init_dt_add_memory_arch */
1096 of_scan_flat_dt(early_init_dt_scan_memory, NULL);
1097}
1098
1099bool __init early_init_dt_scan(void *params)
1100{
1101 bool status;
1102
1103 status = early_init_dt_verify(params);
1104 if (!status)
1105 return false;
1106
1107 early_init_dt_scan_nodes();
1108 return true;
1109}
1110
1111/**
1112 * unflatten_device_tree - create tree of device_nodes from flat blob
1113 *
1114 * unflattens the device-tree passed by the firmware, creating the
1115 * tree of struct device_node. It also fills the "name" and "type"
1116 * pointers of the nodes so the normal device-tree walking functions
1117 * can be used.
1118 */
1119void __init unflatten_device_tree(void)
1120{
1121 __unflatten_device_tree(initial_boot_params, &of_root,
1122 early_init_dt_alloc_memory_arch);
1123
1124 /* Get pointer to "/chosen" and "/aliases" nodes for use everywhere */
1125 of_alias_scan(early_init_dt_alloc_memory_arch);
1126}
1127
1128/**
1129 * unflatten_and_copy_device_tree - copy and create tree of device_nodes from flat blob
1130 *
1131 * Copies and unflattens the device-tree passed by the firmware, creating the
1132 * tree of struct device_node. It also fills the "name" and "type"
1133 * pointers of the nodes so the normal device-tree walking functions
1134 * can be used. This should only be used when the FDT memory has not been
1135 * reserved such is the case when the FDT is built-in to the kernel init
1136 * section. If the FDT memory is reserved already then unflatten_device_tree
1137 * should be used instead.
1138 */
1139void __init unflatten_and_copy_device_tree(void)
1140{
1141 int size;
1142 void *dt;
1143
1144 if (!initial_boot_params) {
1145 pr_warn("No valid device tree found, continuing without\n");
1146 return;
1147 }
1148
1149 size = fdt_totalsize(initial_boot_params);
1150 dt = early_init_dt_alloc_memory_arch(size,
1151 roundup_pow_of_two(FDT_V17_SIZE));
1152
1153 if (dt) {
1154 memcpy(dt, initial_boot_params, size);
1155 initial_boot_params = dt;
1156 }
1157 unflatten_device_tree();
1158}
1159
1160#ifdef CONFIG_SYSFS
1161static ssize_t of_fdt_raw_read(struct file *filp, struct kobject *kobj,
1162 struct bin_attribute *bin_attr,
1163 char *buf, loff_t off, size_t count)
1164{
1165 memcpy(buf, initial_boot_params + off, count);
1166 return count;
1167}
1168
1169static int __init of_fdt_raw_init(void)
1170{
1171 static struct bin_attribute of_fdt_raw_attr =
1172 __BIN_ATTR(fdt, S_IRUSR, of_fdt_raw_read, NULL, 0);
1173
1174 if (!initial_boot_params)
1175 return 0;
1176
1177 if (of_fdt_crc32 != crc32_be(~0, initial_boot_params,
1178 fdt_totalsize(initial_boot_params))) {
1179 pr_warn("fdt: not creating '/sys/firmware/fdt': CRC check failed\n");
1180 return 0;
1181 }
1182 of_fdt_raw_attr.size = fdt_totalsize(initial_boot_params);
1183 return sysfs_create_bin_file(firmware_kobj, &of_fdt_raw_attr);
1184}
1185late_initcall(of_fdt_raw_init);
1186#endif
1187
1188#endif /* CONFIG_OF_EARLY_FLATTREE */