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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Functions for working with the Flattened Device Tree data format
4 *
5 * Copyright 2009 Benjamin Herrenschmidt, IBM Corp
6 * benh@kernel.crashing.org
7 */
8
9#define pr_fmt(fmt) "OF: fdt: " fmt
10
11#include <linux/crash_dump.h>
12#include <linux/crc32.h>
13#include <linux/kernel.h>
14#include <linux/initrd.h>
15#include <linux/memblock.h>
16#include <linux/mutex.h>
17#include <linux/of.h>
18#include <linux/of_fdt.h>
19#include <linux/of_reserved_mem.h>
20#include <linux/sizes.h>
21#include <linux/string.h>
22#include <linux/errno.h>
23#include <linux/slab.h>
24#include <linux/libfdt.h>
25#include <linux/debugfs.h>
26#include <linux/serial_core.h>
27#include <linux/sysfs.h>
28#include <linux/random.h>
29
30#include <asm/setup.h> /* for COMMAND_LINE_SIZE */
31#include <asm/page.h>
32
33#include "of_private.h"
34
35/*
36 * of_fdt_limit_memory - limit the number of regions in the /memory node
37 * @limit: maximum entries
38 *
39 * Adjust the flattened device tree to have at most 'limit' number of
40 * memory entries in the /memory node. This function may be called
41 * any time after initial_boot_param is set.
42 */
43void __init of_fdt_limit_memory(int limit)
44{
45 int memory;
46 int len;
47 const void *val;
48 int nr_address_cells = OF_ROOT_NODE_ADDR_CELLS_DEFAULT;
49 int nr_size_cells = OF_ROOT_NODE_SIZE_CELLS_DEFAULT;
50 const __be32 *addr_prop;
51 const __be32 *size_prop;
52 int root_offset;
53 int cell_size;
54
55 root_offset = fdt_path_offset(initial_boot_params, "/");
56 if (root_offset < 0)
57 return;
58
59 addr_prop = fdt_getprop(initial_boot_params, root_offset,
60 "#address-cells", NULL);
61 if (addr_prop)
62 nr_address_cells = fdt32_to_cpu(*addr_prop);
63
64 size_prop = fdt_getprop(initial_boot_params, root_offset,
65 "#size-cells", NULL);
66 if (size_prop)
67 nr_size_cells = fdt32_to_cpu(*size_prop);
68
69 cell_size = sizeof(uint32_t)*(nr_address_cells + nr_size_cells);
70
71 memory = fdt_path_offset(initial_boot_params, "/memory");
72 if (memory > 0) {
73 val = fdt_getprop(initial_boot_params, memory, "reg", &len);
74 if (len > limit*cell_size) {
75 len = limit*cell_size;
76 pr_debug("Limiting number of entries to %d\n", limit);
77 fdt_setprop(initial_boot_params, memory, "reg", val,
78 len);
79 }
80 }
81}
82
83static bool of_fdt_device_is_available(const void *blob, unsigned long node)
84{
85 const char *status = fdt_getprop(blob, node, "status", NULL);
86
87 if (!status)
88 return true;
89
90 if (!strcmp(status, "ok") || !strcmp(status, "okay"))
91 return true;
92
93 return false;
94}
95
96static void *unflatten_dt_alloc(void **mem, unsigned long size,
97 unsigned long align)
98{
99 void *res;
100
101 *mem = PTR_ALIGN(*mem, align);
102 res = *mem;
103 *mem += size;
104
105 return res;
106}
107
108static void populate_properties(const void *blob,
109 int offset,
110 void **mem,
111 struct device_node *np,
112 const char *nodename,
113 bool dryrun)
114{
115 struct property *pp, **pprev = NULL;
116 int cur;
117 bool has_name = false;
118
119 pprev = &np->properties;
120 for (cur = fdt_first_property_offset(blob, offset);
121 cur >= 0;
122 cur = fdt_next_property_offset(blob, cur)) {
123 const __be32 *val;
124 const char *pname;
125 u32 sz;
126
127 val = fdt_getprop_by_offset(blob, cur, &pname, &sz);
128 if (!val) {
129 pr_warn("Cannot locate property at 0x%x\n", cur);
130 continue;
131 }
132
133 if (!pname) {
134 pr_warn("Cannot find property name at 0x%x\n", cur);
135 continue;
136 }
137
138 if (!strcmp(pname, "name"))
139 has_name = true;
140
141 pp = unflatten_dt_alloc(mem, sizeof(struct property),
142 __alignof__(struct property));
143 if (dryrun)
144 continue;
145
146 /* We accept flattened tree phandles either in
147 * ePAPR-style "phandle" properties, or the
148 * legacy "linux,phandle" properties. If both
149 * appear and have different values, things
150 * will get weird. Don't do that.
151 */
152 if (!strcmp(pname, "phandle") ||
153 !strcmp(pname, "linux,phandle")) {
154 if (!np->phandle)
155 np->phandle = be32_to_cpup(val);
156 }
157
158 /* And we process the "ibm,phandle" property
159 * used in pSeries dynamic device tree
160 * stuff
161 */
162 if (!strcmp(pname, "ibm,phandle"))
163 np->phandle = be32_to_cpup(val);
164
165 pp->name = (char *)pname;
166 pp->length = sz;
167 pp->value = (__be32 *)val;
168 *pprev = pp;
169 pprev = &pp->next;
170 }
171
172 /* With version 0x10 we may not have the name property,
173 * recreate it here from the unit name if absent
174 */
175 if (!has_name) {
176 const char *p = nodename, *ps = p, *pa = NULL;
177 int len;
178
179 while (*p) {
180 if ((*p) == '@')
181 pa = p;
182 else if ((*p) == '/')
183 ps = p + 1;
184 p++;
185 }
186
187 if (pa < ps)
188 pa = p;
189 len = (pa - ps) + 1;
190 pp = unflatten_dt_alloc(mem, sizeof(struct property) + len,
191 __alignof__(struct property));
192 if (!dryrun) {
193 pp->name = "name";
194 pp->length = len;
195 pp->value = pp + 1;
196 *pprev = pp;
197 memcpy(pp->value, ps, len - 1);
198 ((char *)pp->value)[len - 1] = 0;
199 pr_debug("fixed up name for %s -> %s\n",
200 nodename, (char *)pp->value);
201 }
202 }
203}
204
205static int populate_node(const void *blob,
206 int offset,
207 void **mem,
208 struct device_node *dad,
209 struct device_node **pnp,
210 bool dryrun)
211{
212 struct device_node *np;
213 const char *pathp;
214 int len;
215
216 pathp = fdt_get_name(blob, offset, &len);
217 if (!pathp) {
218 *pnp = NULL;
219 return len;
220 }
221
222 len++;
223
224 np = unflatten_dt_alloc(mem, sizeof(struct device_node) + len,
225 __alignof__(struct device_node));
226 if (!dryrun) {
227 char *fn;
228 of_node_init(np);
229 np->full_name = fn = ((char *)np) + sizeof(*np);
230
231 memcpy(fn, pathp, len);
232
233 if (dad != NULL) {
234 np->parent = dad;
235 np->sibling = dad->child;
236 dad->child = np;
237 }
238 }
239
240 populate_properties(blob, offset, mem, np, pathp, dryrun);
241 if (!dryrun) {
242 np->name = of_get_property(np, "name", NULL);
243 if (!np->name)
244 np->name = "<NULL>";
245 }
246
247 *pnp = np;
248 return 0;
249}
250
251static void reverse_nodes(struct device_node *parent)
252{
253 struct device_node *child, *next;
254
255 /* In-depth first */
256 child = parent->child;
257 while (child) {
258 reverse_nodes(child);
259
260 child = child->sibling;
261 }
262
263 /* Reverse the nodes in the child list */
264 child = parent->child;
265 parent->child = NULL;
266 while (child) {
267 next = child->sibling;
268
269 child->sibling = parent->child;
270 parent->child = child;
271 child = next;
272 }
273}
274
275/**
276 * unflatten_dt_nodes - Alloc and populate a device_node from the flat tree
277 * @blob: The parent device tree blob
278 * @mem: Memory chunk to use for allocating device nodes and properties
279 * @dad: Parent struct device_node
280 * @nodepp: The device_node tree created by the call
281 *
282 * Return: The size of unflattened device tree or error code
283 */
284static int unflatten_dt_nodes(const void *blob,
285 void *mem,
286 struct device_node *dad,
287 struct device_node **nodepp)
288{
289 struct device_node *root;
290 int offset = 0, depth = 0, initial_depth = 0;
291#define FDT_MAX_DEPTH 64
292 struct device_node *nps[FDT_MAX_DEPTH];
293 void *base = mem;
294 bool dryrun = !base;
295 int ret;
296
297 if (nodepp)
298 *nodepp = NULL;
299
300 /*
301 * We're unflattening device sub-tree if @dad is valid. There are
302 * possibly multiple nodes in the first level of depth. We need
303 * set @depth to 1 to make fdt_next_node() happy as it bails
304 * immediately when negative @depth is found. Otherwise, the device
305 * nodes except the first one won't be unflattened successfully.
306 */
307 if (dad)
308 depth = initial_depth = 1;
309
310 root = dad;
311 nps[depth] = dad;
312
313 for (offset = 0;
314 offset >= 0 && depth >= initial_depth;
315 offset = fdt_next_node(blob, offset, &depth)) {
316 if (WARN_ON_ONCE(depth >= FDT_MAX_DEPTH - 1))
317 continue;
318
319 if (!IS_ENABLED(CONFIG_OF_KOBJ) &&
320 !of_fdt_device_is_available(blob, offset))
321 continue;
322
323 ret = populate_node(blob, offset, &mem, nps[depth],
324 &nps[depth+1], dryrun);
325 if (ret < 0)
326 return ret;
327
328 if (!dryrun && nodepp && !*nodepp)
329 *nodepp = nps[depth+1];
330 if (!dryrun && !root)
331 root = nps[depth+1];
332 }
333
334 if (offset < 0 && offset != -FDT_ERR_NOTFOUND) {
335 pr_err("Error %d processing FDT\n", offset);
336 return -EINVAL;
337 }
338
339 /*
340 * Reverse the child list. Some drivers assumes node order matches .dts
341 * node order
342 */
343 if (!dryrun)
344 reverse_nodes(root);
345
346 return mem - base;
347}
348
349/**
350 * __unflatten_device_tree - create tree of device_nodes from flat blob
351 * @blob: The blob to expand
352 * @dad: Parent device node
353 * @mynodes: The device_node tree created by the call
354 * @dt_alloc: An allocator that provides a virtual address to memory
355 * for the resulting tree
356 * @detached: if true set OF_DETACHED on @mynodes
357 *
358 * unflattens a device-tree, creating the tree of struct device_node. It also
359 * fills the "name" and "type" pointers of the nodes so the normal device-tree
360 * walking functions can be used.
361 *
362 * Return: NULL on failure or the memory chunk containing the unflattened
363 * device tree on success.
364 */
365void *__unflatten_device_tree(const void *blob,
366 struct device_node *dad,
367 struct device_node **mynodes,
368 void *(*dt_alloc)(u64 size, u64 align),
369 bool detached)
370{
371 int size;
372 void *mem;
373 int ret;
374
375 if (mynodes)
376 *mynodes = NULL;
377
378 pr_debug(" -> unflatten_device_tree()\n");
379
380 if (!blob) {
381 pr_debug("No device tree pointer\n");
382 return NULL;
383 }
384
385 pr_debug("Unflattening device tree:\n");
386 pr_debug("magic: %08x\n", fdt_magic(blob));
387 pr_debug("size: %08x\n", fdt_totalsize(blob));
388 pr_debug("version: %08x\n", fdt_version(blob));
389
390 if (fdt_check_header(blob)) {
391 pr_err("Invalid device tree blob header\n");
392 return NULL;
393 }
394
395 /* First pass, scan for size */
396 size = unflatten_dt_nodes(blob, NULL, dad, NULL);
397 if (size <= 0)
398 return NULL;
399
400 size = ALIGN(size, 4);
401 pr_debug(" size is %d, allocating...\n", size);
402
403 /* Allocate memory for the expanded device tree */
404 mem = dt_alloc(size + 4, __alignof__(struct device_node));
405 if (!mem)
406 return NULL;
407
408 memset(mem, 0, size);
409
410 *(__be32 *)(mem + size) = cpu_to_be32(0xdeadbeef);
411
412 pr_debug(" unflattening %p...\n", mem);
413
414 /* Second pass, do actual unflattening */
415 ret = unflatten_dt_nodes(blob, mem, dad, mynodes);
416
417 if (be32_to_cpup(mem + size) != 0xdeadbeef)
418 pr_warn("End of tree marker overwritten: %08x\n",
419 be32_to_cpup(mem + size));
420
421 if (ret <= 0)
422 return NULL;
423
424 if (detached && mynodes && *mynodes) {
425 of_node_set_flag(*mynodes, OF_DETACHED);
426 pr_debug("unflattened tree is detached\n");
427 }
428
429 pr_debug(" <- unflatten_device_tree()\n");
430 return mem;
431}
432
433static void *kernel_tree_alloc(u64 size, u64 align)
434{
435 return kzalloc(size, GFP_KERNEL);
436}
437
438static DEFINE_MUTEX(of_fdt_unflatten_mutex);
439
440/**
441 * of_fdt_unflatten_tree - create tree of device_nodes from flat blob
442 * @blob: Flat device tree blob
443 * @dad: Parent device node
444 * @mynodes: The device tree created by the call
445 *
446 * unflattens the device-tree passed by the firmware, creating the
447 * tree of struct device_node. It also fills the "name" and "type"
448 * pointers of the nodes so the normal device-tree walking functions
449 * can be used.
450 *
451 * Return: NULL on failure or the memory chunk containing the unflattened
452 * device tree on success.
453 */
454void *of_fdt_unflatten_tree(const unsigned long *blob,
455 struct device_node *dad,
456 struct device_node **mynodes)
457{
458 void *mem;
459
460 mutex_lock(&of_fdt_unflatten_mutex);
461 mem = __unflatten_device_tree(blob, dad, mynodes, &kernel_tree_alloc,
462 true);
463 mutex_unlock(&of_fdt_unflatten_mutex);
464
465 return mem;
466}
467EXPORT_SYMBOL_GPL(of_fdt_unflatten_tree);
468
469/* Everything below here references initial_boot_params directly. */
470int __initdata dt_root_addr_cells;
471int __initdata dt_root_size_cells;
472
473void *initial_boot_params __ro_after_init;
474
475#ifdef CONFIG_OF_EARLY_FLATTREE
476
477static u32 of_fdt_crc32;
478
479static int __init early_init_dt_reserve_memory(phys_addr_t base,
480 phys_addr_t size, bool nomap)
481{
482 if (nomap) {
483 /*
484 * If the memory is already reserved (by another region), we
485 * should not allow it to be marked nomap, but don't worry
486 * if the region isn't memory as it won't be mapped.
487 */
488 if (memblock_overlaps_region(&memblock.memory, base, size) &&
489 memblock_is_region_reserved(base, size))
490 return -EBUSY;
491
492 return memblock_mark_nomap(base, size);
493 }
494 return memblock_reserve(base, size);
495}
496
497/*
498 * __reserved_mem_reserve_reg() - reserve all memory described in 'reg' property
499 */
500static int __init __reserved_mem_reserve_reg(unsigned long node,
501 const char *uname)
502{
503 int t_len = (dt_root_addr_cells + dt_root_size_cells) * sizeof(__be32);
504 phys_addr_t base, size;
505 int len;
506 const __be32 *prop;
507 int first = 1;
508 bool nomap;
509
510 prop = of_get_flat_dt_prop(node, "reg", &len);
511 if (!prop)
512 return -ENOENT;
513
514 if (len && len % t_len != 0) {
515 pr_err("Reserved memory: invalid reg property in '%s', skipping node.\n",
516 uname);
517 return -EINVAL;
518 }
519
520 nomap = of_get_flat_dt_prop(node, "no-map", NULL) != NULL;
521
522 while (len >= t_len) {
523 base = dt_mem_next_cell(dt_root_addr_cells, &prop);
524 size = dt_mem_next_cell(dt_root_size_cells, &prop);
525
526 if (size &&
527 early_init_dt_reserve_memory(base, size, nomap) == 0)
528 pr_debug("Reserved memory: reserved region for node '%s': base %pa, size %lu MiB\n",
529 uname, &base, (unsigned long)(size / SZ_1M));
530 else
531 pr_err("Reserved memory: failed to reserve memory for node '%s': base %pa, size %lu MiB\n",
532 uname, &base, (unsigned long)(size / SZ_1M));
533
534 len -= t_len;
535 if (first) {
536 fdt_reserved_mem_save_node(node, uname, base, size);
537 first = 0;
538 }
539 }
540 return 0;
541}
542
543/*
544 * __reserved_mem_check_root() - check if #size-cells, #address-cells provided
545 * in /reserved-memory matches the values supported by the current implementation,
546 * also check if ranges property has been provided
547 */
548static int __init __reserved_mem_check_root(unsigned long node)
549{
550 const __be32 *prop;
551
552 prop = of_get_flat_dt_prop(node, "#size-cells", NULL);
553 if (!prop || be32_to_cpup(prop) != dt_root_size_cells)
554 return -EINVAL;
555
556 prop = of_get_flat_dt_prop(node, "#address-cells", NULL);
557 if (!prop || be32_to_cpup(prop) != dt_root_addr_cells)
558 return -EINVAL;
559
560 prop = of_get_flat_dt_prop(node, "ranges", NULL);
561 if (!prop)
562 return -EINVAL;
563 return 0;
564}
565
566/*
567 * fdt_scan_reserved_mem() - scan a single FDT node for reserved memory
568 */
569static int __init fdt_scan_reserved_mem(void)
570{
571 int node, child;
572 const void *fdt = initial_boot_params;
573
574 node = fdt_path_offset(fdt, "/reserved-memory");
575 if (node < 0)
576 return -ENODEV;
577
578 if (__reserved_mem_check_root(node) != 0) {
579 pr_err("Reserved memory: unsupported node format, ignoring\n");
580 return -EINVAL;
581 }
582
583 fdt_for_each_subnode(child, fdt, node) {
584 const char *uname;
585 int err;
586
587 if (!of_fdt_device_is_available(fdt, child))
588 continue;
589
590 uname = fdt_get_name(fdt, child, NULL);
591
592 err = __reserved_mem_reserve_reg(child, uname);
593 if (err == -ENOENT && of_get_flat_dt_prop(child, "size", NULL))
594 fdt_reserved_mem_save_node(child, uname, 0, 0);
595 }
596 return 0;
597}
598
599/*
600 * fdt_reserve_elfcorehdr() - reserves memory for elf core header
601 *
602 * This function reserves the memory occupied by an elf core header
603 * described in the device tree. This region contains all the
604 * information about primary kernel's core image and is used by a dump
605 * capture kernel to access the system memory on primary kernel.
606 */
607static void __init fdt_reserve_elfcorehdr(void)
608{
609 if (!IS_ENABLED(CONFIG_CRASH_DUMP) || !elfcorehdr_size)
610 return;
611
612 if (memblock_is_region_reserved(elfcorehdr_addr, elfcorehdr_size)) {
613 pr_warn("elfcorehdr is overlapped\n");
614 return;
615 }
616
617 memblock_reserve(elfcorehdr_addr, elfcorehdr_size);
618
619 pr_info("Reserving %llu KiB of memory at 0x%llx for elfcorehdr\n",
620 elfcorehdr_size >> 10, elfcorehdr_addr);
621}
622
623/**
624 * early_init_fdt_scan_reserved_mem() - create reserved memory regions
625 *
626 * This function grabs memory from early allocator for device exclusive use
627 * defined in device tree structures. It should be called by arch specific code
628 * once the early allocator (i.e. memblock) has been fully activated.
629 */
630void __init early_init_fdt_scan_reserved_mem(void)
631{
632 int n;
633 u64 base, size;
634
635 if (!initial_boot_params)
636 return;
637
638 /* Process header /memreserve/ fields */
639 for (n = 0; ; n++) {
640 fdt_get_mem_rsv(initial_boot_params, n, &base, &size);
641 if (!size)
642 break;
643 memblock_reserve(base, size);
644 }
645
646 fdt_scan_reserved_mem();
647 fdt_reserve_elfcorehdr();
648 fdt_init_reserved_mem();
649}
650
651/**
652 * early_init_fdt_reserve_self() - reserve the memory used by the FDT blob
653 */
654void __init early_init_fdt_reserve_self(void)
655{
656 if (!initial_boot_params)
657 return;
658
659 /* Reserve the dtb region */
660 memblock_reserve(__pa(initial_boot_params),
661 fdt_totalsize(initial_boot_params));
662}
663
664/**
665 * of_scan_flat_dt - scan flattened tree blob and call callback on each.
666 * @it: callback function
667 * @data: context data pointer
668 *
669 * This function is used to scan the flattened device-tree, it is
670 * used to extract the memory information at boot before we can
671 * unflatten the tree
672 */
673int __init of_scan_flat_dt(int (*it)(unsigned long node,
674 const char *uname, int depth,
675 void *data),
676 void *data)
677{
678 const void *blob = initial_boot_params;
679 const char *pathp;
680 int offset, rc = 0, depth = -1;
681
682 if (!blob)
683 return 0;
684
685 for (offset = fdt_next_node(blob, -1, &depth);
686 offset >= 0 && depth >= 0 && !rc;
687 offset = fdt_next_node(blob, offset, &depth)) {
688
689 pathp = fdt_get_name(blob, offset, NULL);
690 rc = it(offset, pathp, depth, data);
691 }
692 return rc;
693}
694
695/**
696 * of_scan_flat_dt_subnodes - scan sub-nodes of a node call callback on each.
697 * @parent: parent node
698 * @it: callback function
699 * @data: context data pointer
700 *
701 * This function is used to scan sub-nodes of a node.
702 */
703int __init of_scan_flat_dt_subnodes(unsigned long parent,
704 int (*it)(unsigned long node,
705 const char *uname,
706 void *data),
707 void *data)
708{
709 const void *blob = initial_boot_params;
710 int node;
711
712 fdt_for_each_subnode(node, blob, parent) {
713 const char *pathp;
714 int rc;
715
716 pathp = fdt_get_name(blob, node, NULL);
717 rc = it(node, pathp, data);
718 if (rc)
719 return rc;
720 }
721 return 0;
722}
723
724/**
725 * of_get_flat_dt_subnode_by_name - get the subnode by given name
726 *
727 * @node: the parent node
728 * @uname: the name of subnode
729 * @return offset of the subnode, or -FDT_ERR_NOTFOUND if there is none
730 */
731
732int __init of_get_flat_dt_subnode_by_name(unsigned long node, const char *uname)
733{
734 return fdt_subnode_offset(initial_boot_params, node, uname);
735}
736
737/*
738 * of_get_flat_dt_root - find the root node in the flat blob
739 */
740unsigned long __init of_get_flat_dt_root(void)
741{
742 return 0;
743}
744
745/*
746 * of_get_flat_dt_prop - Given a node in the flat blob, return the property ptr
747 *
748 * This function can be used within scan_flattened_dt callback to get
749 * access to properties
750 */
751const void *__init of_get_flat_dt_prop(unsigned long node, const char *name,
752 int *size)
753{
754 return fdt_getprop(initial_boot_params, node, name, size);
755}
756
757/**
758 * of_fdt_is_compatible - Return true if given node from the given blob has
759 * compat in its compatible list
760 * @blob: A device tree blob
761 * @node: node to test
762 * @compat: compatible string to compare with compatible list.
763 *
764 * Return: a non-zero value on match with smaller values returned for more
765 * specific compatible values.
766 */
767static int of_fdt_is_compatible(const void *blob,
768 unsigned long node, const char *compat)
769{
770 const char *cp;
771 int cplen;
772 unsigned long l, score = 0;
773
774 cp = fdt_getprop(blob, node, "compatible", &cplen);
775 if (cp == NULL)
776 return 0;
777 while (cplen > 0) {
778 score++;
779 if (of_compat_cmp(cp, compat, strlen(compat)) == 0)
780 return score;
781 l = strlen(cp) + 1;
782 cp += l;
783 cplen -= l;
784 }
785
786 return 0;
787}
788
789/**
790 * of_flat_dt_is_compatible - Return true if given node has compat in compatible list
791 * @node: node to test
792 * @compat: compatible string to compare with compatible list.
793 */
794int __init of_flat_dt_is_compatible(unsigned long node, const char *compat)
795{
796 return of_fdt_is_compatible(initial_boot_params, node, compat);
797}
798
799/*
800 * of_flat_dt_match - Return true if node matches a list of compatible values
801 */
802static int __init of_flat_dt_match(unsigned long node, const char *const *compat)
803{
804 unsigned int tmp, score = 0;
805
806 if (!compat)
807 return 0;
808
809 while (*compat) {
810 tmp = of_fdt_is_compatible(initial_boot_params, node, *compat);
811 if (tmp && (score == 0 || (tmp < score)))
812 score = tmp;
813 compat++;
814 }
815
816 return score;
817}
818
819/*
820 * of_get_flat_dt_phandle - Given a node in the flat blob, return the phandle
821 */
822uint32_t __init of_get_flat_dt_phandle(unsigned long node)
823{
824 return fdt_get_phandle(initial_boot_params, node);
825}
826
827const char * __init of_flat_dt_get_machine_name(void)
828{
829 const char *name;
830 unsigned long dt_root = of_get_flat_dt_root();
831
832 name = of_get_flat_dt_prop(dt_root, "model", NULL);
833 if (!name)
834 name = of_get_flat_dt_prop(dt_root, "compatible", NULL);
835 return name;
836}
837
838/**
839 * of_flat_dt_match_machine - Iterate match tables to find matching machine.
840 *
841 * @default_match: A machine specific ptr to return in case of no match.
842 * @get_next_compat: callback function to return next compatible match table.
843 *
844 * Iterate through machine match tables to find the best match for the machine
845 * compatible string in the FDT.
846 */
847const void * __init of_flat_dt_match_machine(const void *default_match,
848 const void * (*get_next_compat)(const char * const**))
849{
850 const void *data = NULL;
851 const void *best_data = default_match;
852 const char *const *compat;
853 unsigned long dt_root;
854 unsigned int best_score = ~1, score = 0;
855
856 dt_root = of_get_flat_dt_root();
857 while ((data = get_next_compat(&compat))) {
858 score = of_flat_dt_match(dt_root, compat);
859 if (score > 0 && score < best_score) {
860 best_data = data;
861 best_score = score;
862 }
863 }
864 if (!best_data) {
865 const char *prop;
866 int size;
867
868 pr_err("\n unrecognized device tree list:\n[ ");
869
870 prop = of_get_flat_dt_prop(dt_root, "compatible", &size);
871 if (prop) {
872 while (size > 0) {
873 printk("'%s' ", prop);
874 size -= strlen(prop) + 1;
875 prop += strlen(prop) + 1;
876 }
877 }
878 printk("]\n\n");
879 return NULL;
880 }
881
882 pr_info("Machine model: %s\n", of_flat_dt_get_machine_name());
883
884 return best_data;
885}
886
887static void __early_init_dt_declare_initrd(unsigned long start,
888 unsigned long end)
889{
890 /* ARM64 would cause a BUG to occur here when CONFIG_DEBUG_VM is
891 * enabled since __va() is called too early. ARM64 does make use
892 * of phys_initrd_start/phys_initrd_size so we can skip this
893 * conversion.
894 */
895 if (!IS_ENABLED(CONFIG_ARM64)) {
896 initrd_start = (unsigned long)__va(start);
897 initrd_end = (unsigned long)__va(end);
898 initrd_below_start_ok = 1;
899 }
900}
901
902/**
903 * early_init_dt_check_for_initrd - Decode initrd location from flat tree
904 * @node: reference to node containing initrd location ('chosen')
905 */
906static void __init early_init_dt_check_for_initrd(unsigned long node)
907{
908 u64 start, end;
909 int len;
910 const __be32 *prop;
911
912 if (!IS_ENABLED(CONFIG_BLK_DEV_INITRD))
913 return;
914
915 pr_debug("Looking for initrd properties... ");
916
917 prop = of_get_flat_dt_prop(node, "linux,initrd-start", &len);
918 if (!prop)
919 return;
920 start = of_read_number(prop, len/4);
921
922 prop = of_get_flat_dt_prop(node, "linux,initrd-end", &len);
923 if (!prop)
924 return;
925 end = of_read_number(prop, len/4);
926 if (start > end)
927 return;
928
929 __early_init_dt_declare_initrd(start, end);
930 phys_initrd_start = start;
931 phys_initrd_size = end - start;
932
933 pr_debug("initrd_start=0x%llx initrd_end=0x%llx\n", start, end);
934}
935
936/**
937 * early_init_dt_check_for_elfcorehdr - Decode elfcorehdr location from flat
938 * tree
939 * @node: reference to node containing elfcorehdr location ('chosen')
940 */
941static void __init early_init_dt_check_for_elfcorehdr(unsigned long node)
942{
943 const __be32 *prop;
944 int len;
945
946 if (!IS_ENABLED(CONFIG_CRASH_DUMP))
947 return;
948
949 pr_debug("Looking for elfcorehdr property... ");
950
951 prop = of_get_flat_dt_prop(node, "linux,elfcorehdr", &len);
952 if (!prop || (len < (dt_root_addr_cells + dt_root_size_cells)))
953 return;
954
955 elfcorehdr_addr = dt_mem_next_cell(dt_root_addr_cells, &prop);
956 elfcorehdr_size = dt_mem_next_cell(dt_root_size_cells, &prop);
957
958 pr_debug("elfcorehdr_start=0x%llx elfcorehdr_size=0x%llx\n",
959 elfcorehdr_addr, elfcorehdr_size);
960}
961
962static unsigned long chosen_node_offset = -FDT_ERR_NOTFOUND;
963
964/*
965 * The main usage of linux,usable-memory-range is for crash dump kernel.
966 * Originally, the number of usable-memory regions is one. Now there may
967 * be two regions, low region and high region.
968 * To make compatibility with existing user-space and older kdump, the low
969 * region is always the last range of linux,usable-memory-range if exist.
970 */
971#define MAX_USABLE_RANGES 2
972
973/**
974 * early_init_dt_check_for_usable_mem_range - Decode usable memory range
975 * location from flat tree
976 */
977void __init early_init_dt_check_for_usable_mem_range(void)
978{
979 struct memblock_region rgn[MAX_USABLE_RANGES] = {0};
980 const __be32 *prop, *endp;
981 int len, i;
982 unsigned long node = chosen_node_offset;
983
984 if ((long)node < 0)
985 return;
986
987 pr_debug("Looking for usable-memory-range property... ");
988
989 prop = of_get_flat_dt_prop(node, "linux,usable-memory-range", &len);
990 if (!prop || (len % (dt_root_addr_cells + dt_root_size_cells)))
991 return;
992
993 endp = prop + (len / sizeof(__be32));
994 for (i = 0; i < MAX_USABLE_RANGES && prop < endp; i++) {
995 rgn[i].base = dt_mem_next_cell(dt_root_addr_cells, &prop);
996 rgn[i].size = dt_mem_next_cell(dt_root_size_cells, &prop);
997
998 pr_debug("cap_mem_regions[%d]: base=%pa, size=%pa\n",
999 i, &rgn[i].base, &rgn[i].size);
1000 }
1001
1002 memblock_cap_memory_range(rgn[0].base, rgn[0].size);
1003 for (i = 1; i < MAX_USABLE_RANGES && rgn[i].size; i++)
1004 memblock_add(rgn[i].base, rgn[i].size);
1005}
1006
1007#ifdef CONFIG_SERIAL_EARLYCON
1008
1009int __init early_init_dt_scan_chosen_stdout(void)
1010{
1011 int offset;
1012 const char *p, *q, *options = NULL;
1013 int l;
1014 const struct earlycon_id *match;
1015 const void *fdt = initial_boot_params;
1016 int ret;
1017
1018 offset = fdt_path_offset(fdt, "/chosen");
1019 if (offset < 0)
1020 offset = fdt_path_offset(fdt, "/chosen@0");
1021 if (offset < 0)
1022 return -ENOENT;
1023
1024 p = fdt_getprop(fdt, offset, "stdout-path", &l);
1025 if (!p)
1026 p = fdt_getprop(fdt, offset, "linux,stdout-path", &l);
1027 if (!p || !l)
1028 return -ENOENT;
1029
1030 q = strchrnul(p, ':');
1031 if (*q != '\0')
1032 options = q + 1;
1033 l = q - p;
1034
1035 /* Get the node specified by stdout-path */
1036 offset = fdt_path_offset_namelen(fdt, p, l);
1037 if (offset < 0) {
1038 pr_warn("earlycon: stdout-path %.*s not found\n", l, p);
1039 return 0;
1040 }
1041
1042 for (match = __earlycon_table; match < __earlycon_table_end; match++) {
1043 if (!match->compatible[0])
1044 continue;
1045
1046 if (fdt_node_check_compatible(fdt, offset, match->compatible))
1047 continue;
1048
1049 ret = of_setup_earlycon(match, offset, options);
1050 if (!ret || ret == -EALREADY)
1051 return 0;
1052 }
1053 return -ENODEV;
1054}
1055#endif
1056
1057/*
1058 * early_init_dt_scan_root - fetch the top level address and size cells
1059 */
1060int __init early_init_dt_scan_root(void)
1061{
1062 const __be32 *prop;
1063 const void *fdt = initial_boot_params;
1064 int node = fdt_path_offset(fdt, "/");
1065
1066 if (node < 0)
1067 return -ENODEV;
1068
1069 dt_root_size_cells = OF_ROOT_NODE_SIZE_CELLS_DEFAULT;
1070 dt_root_addr_cells = OF_ROOT_NODE_ADDR_CELLS_DEFAULT;
1071
1072 prop = of_get_flat_dt_prop(node, "#size-cells", NULL);
1073 if (prop)
1074 dt_root_size_cells = be32_to_cpup(prop);
1075 pr_debug("dt_root_size_cells = %x\n", dt_root_size_cells);
1076
1077 prop = of_get_flat_dt_prop(node, "#address-cells", NULL);
1078 if (prop)
1079 dt_root_addr_cells = be32_to_cpup(prop);
1080 pr_debug("dt_root_addr_cells = %x\n", dt_root_addr_cells);
1081
1082 return 0;
1083}
1084
1085u64 __init dt_mem_next_cell(int s, const __be32 **cellp)
1086{
1087 const __be32 *p = *cellp;
1088
1089 *cellp = p + s;
1090 return of_read_number(p, s);
1091}
1092
1093/*
1094 * early_init_dt_scan_memory - Look for and parse memory nodes
1095 */
1096int __init early_init_dt_scan_memory(void)
1097{
1098 int node, found_memory = 0;
1099 const void *fdt = initial_boot_params;
1100
1101 fdt_for_each_subnode(node, fdt, 0) {
1102 const char *type = of_get_flat_dt_prop(node, "device_type", NULL);
1103 const __be32 *reg, *endp;
1104 int l;
1105 bool hotpluggable;
1106
1107 /* We are scanning "memory" nodes only */
1108 if (type == NULL || strcmp(type, "memory") != 0)
1109 continue;
1110
1111 if (!of_fdt_device_is_available(fdt, node))
1112 continue;
1113
1114 reg = of_get_flat_dt_prop(node, "linux,usable-memory", &l);
1115 if (reg == NULL)
1116 reg = of_get_flat_dt_prop(node, "reg", &l);
1117 if (reg == NULL)
1118 continue;
1119
1120 endp = reg + (l / sizeof(__be32));
1121 hotpluggable = of_get_flat_dt_prop(node, "hotpluggable", NULL);
1122
1123 pr_debug("memory scan node %s, reg size %d,\n",
1124 fdt_get_name(fdt, node, NULL), l);
1125
1126 while ((endp - reg) >= (dt_root_addr_cells + dt_root_size_cells)) {
1127 u64 base, size;
1128
1129 base = dt_mem_next_cell(dt_root_addr_cells, ®);
1130 size = dt_mem_next_cell(dt_root_size_cells, ®);
1131
1132 if (size == 0)
1133 continue;
1134 pr_debug(" - %llx, %llx\n", base, size);
1135
1136 early_init_dt_add_memory_arch(base, size);
1137
1138 found_memory = 1;
1139
1140 if (!hotpluggable)
1141 continue;
1142
1143 if (memblock_mark_hotplug(base, size))
1144 pr_warn("failed to mark hotplug range 0x%llx - 0x%llx\n",
1145 base, base + size);
1146 }
1147 }
1148 return found_memory;
1149}
1150
1151int __init early_init_dt_scan_chosen(char *cmdline)
1152{
1153 int l, node;
1154 const char *p;
1155 const void *rng_seed;
1156 const void *fdt = initial_boot_params;
1157
1158 node = fdt_path_offset(fdt, "/chosen");
1159 if (node < 0)
1160 node = fdt_path_offset(fdt, "/chosen@0");
1161 if (node < 0)
1162 /* Handle the cmdline config options even if no /chosen node */
1163 goto handle_cmdline;
1164
1165 chosen_node_offset = node;
1166
1167 early_init_dt_check_for_initrd(node);
1168 early_init_dt_check_for_elfcorehdr(node);
1169
1170 rng_seed = of_get_flat_dt_prop(node, "rng-seed", &l);
1171 if (rng_seed && l > 0) {
1172 add_bootloader_randomness(rng_seed, l);
1173
1174 /* try to clear seed so it won't be found. */
1175 fdt_nop_property(initial_boot_params, node, "rng-seed");
1176
1177 /* update CRC check value */
1178 of_fdt_crc32 = crc32_be(~0, initial_boot_params,
1179 fdt_totalsize(initial_boot_params));
1180 }
1181
1182 /* Retrieve command line */
1183 p = of_get_flat_dt_prop(node, "bootargs", &l);
1184 if (p != NULL && l > 0)
1185 strscpy(cmdline, p, min(l, COMMAND_LINE_SIZE));
1186
1187handle_cmdline:
1188 /*
1189 * CONFIG_CMDLINE is meant to be a default in case nothing else
1190 * managed to set the command line, unless CONFIG_CMDLINE_FORCE
1191 * is set in which case we override whatever was found earlier.
1192 */
1193#ifdef CONFIG_CMDLINE
1194#if defined(CONFIG_CMDLINE_EXTEND)
1195 strlcat(cmdline, " ", COMMAND_LINE_SIZE);
1196 strlcat(cmdline, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
1197#elif defined(CONFIG_CMDLINE_FORCE)
1198 strscpy(cmdline, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
1199#else
1200 /* No arguments from boot loader, use kernel's cmdl*/
1201 if (!((char *)cmdline)[0])
1202 strscpy(cmdline, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
1203#endif
1204#endif /* CONFIG_CMDLINE */
1205
1206 pr_debug("Command line is: %s\n", (char *)cmdline);
1207
1208 return 0;
1209}
1210
1211#ifndef MIN_MEMBLOCK_ADDR
1212#define MIN_MEMBLOCK_ADDR __pa(PAGE_OFFSET)
1213#endif
1214#ifndef MAX_MEMBLOCK_ADDR
1215#define MAX_MEMBLOCK_ADDR ((phys_addr_t)~0)
1216#endif
1217
1218void __init __weak early_init_dt_add_memory_arch(u64 base, u64 size)
1219{
1220 const u64 phys_offset = MIN_MEMBLOCK_ADDR;
1221
1222 if (size < PAGE_SIZE - (base & ~PAGE_MASK)) {
1223 pr_warn("Ignoring memory block 0x%llx - 0x%llx\n",
1224 base, base + size);
1225 return;
1226 }
1227
1228 if (!PAGE_ALIGNED(base)) {
1229 size -= PAGE_SIZE - (base & ~PAGE_MASK);
1230 base = PAGE_ALIGN(base);
1231 }
1232 size &= PAGE_MASK;
1233
1234 if (base > MAX_MEMBLOCK_ADDR) {
1235 pr_warn("Ignoring memory block 0x%llx - 0x%llx\n",
1236 base, base + size);
1237 return;
1238 }
1239
1240 if (base + size - 1 > MAX_MEMBLOCK_ADDR) {
1241 pr_warn("Ignoring memory range 0x%llx - 0x%llx\n",
1242 ((u64)MAX_MEMBLOCK_ADDR) + 1, base + size);
1243 size = MAX_MEMBLOCK_ADDR - base + 1;
1244 }
1245
1246 if (base + size < phys_offset) {
1247 pr_warn("Ignoring memory block 0x%llx - 0x%llx\n",
1248 base, base + size);
1249 return;
1250 }
1251 if (base < phys_offset) {
1252 pr_warn("Ignoring memory range 0x%llx - 0x%llx\n",
1253 base, phys_offset);
1254 size -= phys_offset - base;
1255 base = phys_offset;
1256 }
1257 memblock_add(base, size);
1258}
1259
1260static void * __init early_init_dt_alloc_memory_arch(u64 size, u64 align)
1261{
1262 void *ptr = memblock_alloc(size, align);
1263
1264 if (!ptr)
1265 panic("%s: Failed to allocate %llu bytes align=0x%llx\n",
1266 __func__, size, align);
1267
1268 return ptr;
1269}
1270
1271bool __init early_init_dt_verify(void *params)
1272{
1273 if (!params)
1274 return false;
1275
1276 /* check device tree validity */
1277 if (fdt_check_header(params))
1278 return false;
1279
1280 /* Setup flat device-tree pointer */
1281 initial_boot_params = params;
1282 of_fdt_crc32 = crc32_be(~0, initial_boot_params,
1283 fdt_totalsize(initial_boot_params));
1284 return true;
1285}
1286
1287
1288void __init early_init_dt_scan_nodes(void)
1289{
1290 int rc;
1291
1292 /* Initialize {size,address}-cells info */
1293 early_init_dt_scan_root();
1294
1295 /* Retrieve various information from the /chosen node */
1296 rc = early_init_dt_scan_chosen(boot_command_line);
1297 if (rc)
1298 pr_warn("No chosen node found, continuing without\n");
1299
1300 /* Setup memory, calling early_init_dt_add_memory_arch */
1301 early_init_dt_scan_memory();
1302
1303 /* Handle linux,usable-memory-range property */
1304 early_init_dt_check_for_usable_mem_range();
1305}
1306
1307bool __init early_init_dt_scan(void *params)
1308{
1309 bool status;
1310
1311 status = early_init_dt_verify(params);
1312 if (!status)
1313 return false;
1314
1315 early_init_dt_scan_nodes();
1316 return true;
1317}
1318
1319/**
1320 * unflatten_device_tree - create tree of device_nodes from flat blob
1321 *
1322 * unflattens the device-tree passed by the firmware, creating the
1323 * tree of struct device_node. It also fills the "name" and "type"
1324 * pointers of the nodes so the normal device-tree walking functions
1325 * can be used.
1326 */
1327void __init unflatten_device_tree(void)
1328{
1329 __unflatten_device_tree(initial_boot_params, NULL, &of_root,
1330 early_init_dt_alloc_memory_arch, false);
1331
1332 /* Get pointer to "/chosen" and "/aliases" nodes for use everywhere */
1333 of_alias_scan(early_init_dt_alloc_memory_arch);
1334
1335 unittest_unflatten_overlay_base();
1336}
1337
1338/**
1339 * unflatten_and_copy_device_tree - copy and create tree of device_nodes from flat blob
1340 *
1341 * Copies and unflattens the device-tree passed by the firmware, creating the
1342 * tree of struct device_node. It also fills the "name" and "type"
1343 * pointers of the nodes so the normal device-tree walking functions
1344 * can be used. This should only be used when the FDT memory has not been
1345 * reserved such is the case when the FDT is built-in to the kernel init
1346 * section. If the FDT memory is reserved already then unflatten_device_tree
1347 * should be used instead.
1348 */
1349void __init unflatten_and_copy_device_tree(void)
1350{
1351 int size;
1352 void *dt;
1353
1354 if (!initial_boot_params) {
1355 pr_warn("No valid device tree found, continuing without\n");
1356 return;
1357 }
1358
1359 size = fdt_totalsize(initial_boot_params);
1360 dt = early_init_dt_alloc_memory_arch(size,
1361 roundup_pow_of_two(FDT_V17_SIZE));
1362
1363 if (dt) {
1364 memcpy(dt, initial_boot_params, size);
1365 initial_boot_params = dt;
1366 }
1367 unflatten_device_tree();
1368}
1369
1370#ifdef CONFIG_SYSFS
1371static ssize_t of_fdt_raw_read(struct file *filp, struct kobject *kobj,
1372 struct bin_attribute *bin_attr,
1373 char *buf, loff_t off, size_t count)
1374{
1375 memcpy(buf, initial_boot_params + off, count);
1376 return count;
1377}
1378
1379static int __init of_fdt_raw_init(void)
1380{
1381 static struct bin_attribute of_fdt_raw_attr =
1382 __BIN_ATTR(fdt, S_IRUSR, of_fdt_raw_read, NULL, 0);
1383
1384 if (!initial_boot_params)
1385 return 0;
1386
1387 if (of_fdt_crc32 != crc32_be(~0, initial_boot_params,
1388 fdt_totalsize(initial_boot_params))) {
1389 pr_warn("not creating '/sys/firmware/fdt': CRC check failed\n");
1390 return 0;
1391 }
1392 of_fdt_raw_attr.size = fdt_totalsize(initial_boot_params);
1393 return sysfs_create_bin_file(firmware_kobj, &of_fdt_raw_attr);
1394}
1395late_initcall(of_fdt_raw_init);
1396#endif
1397
1398#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 */