2 * Functions for working with the Flattened Device Tree data format
4 * Copyright 2009 Benjamin Herrenschmidt, IBM Corp
5 * benh@kernel.crashing.org
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.
12 #define pr_fmt(fmt) "OF: fdt: " fmt
14 #include <linux/crc32.h>
15 #include <linux/kernel.h>
16 #include <linux/initrd.h>
17 #include <linux/memblock.h>
18 #include <linux/mutex.h>
20 #include <linux/of_fdt.h>
21 #include <linux/of_reserved_mem.h>
22 #include <linux/sizes.h>
23 #include <linux/string.h>
24 #include <linux/errno.h>
25 #include <linux/slab.h>
26 #include <linux/libfdt.h>
27 #include <linux/debugfs.h>
28 #include <linux/serial_core.h>
29 #include <linux/sysfs.h>
31 #include <asm/setup.h> /* for COMMAND_LINE_SIZE */
34 #include "of_private.h"
37 * of_fdt_limit_memory - limit the number of regions in the /memory node
38 * @limit: maximum entries
40 * Adjust the flattened device tree to have at most 'limit' number of
41 * memory entries in the /memory node. This function may be called
42 * any time after initial_boot_param is set.
44 void of_fdt_limit_memory(int limit)
49 int nr_address_cells = OF_ROOT_NODE_ADDR_CELLS_DEFAULT;
50 int nr_size_cells = OF_ROOT_NODE_SIZE_CELLS_DEFAULT;
51 const __be32 *addr_prop;
52 const __be32 *size_prop;
56 root_offset = fdt_path_offset(initial_boot_params, "/");
60 addr_prop = fdt_getprop(initial_boot_params, root_offset,
61 "#address-cells", NULL);
63 nr_address_cells = fdt32_to_cpu(*addr_prop);
65 size_prop = fdt_getprop(initial_boot_params, root_offset,
68 nr_size_cells = fdt32_to_cpu(*size_prop);
70 cell_size = sizeof(uint32_t)*(nr_address_cells + nr_size_cells);
72 memory = fdt_path_offset(initial_boot_params, "/memory");
74 val = fdt_getprop(initial_boot_params, memory, "reg", &len);
75 if (len > limit*cell_size) {
76 len = limit*cell_size;
77 pr_debug("Limiting number of entries to %d\n", limit);
78 fdt_setprop(initial_boot_params, memory, "reg", val,
85 * of_fdt_is_compatible - Return true if given node from the given blob has
86 * compat in its compatible list
87 * @blob: A device tree blob
89 * @compat: compatible string to compare with compatible list.
91 * On match, returns a non-zero value with smaller values returned for more
92 * specific compatible values.
94 static int of_fdt_is_compatible(const void *blob,
95 unsigned long node, const char *compat)
99 unsigned long l, score = 0;
101 cp = fdt_getprop(blob, node, "compatible", &cplen);
106 if (of_compat_cmp(cp, compat, strlen(compat)) == 0)
117 * of_fdt_is_big_endian - Return true if given node needs BE MMIO accesses
118 * @blob: A device tree blob
119 * @node: node to test
121 * Returns true if the node has a "big-endian" property, or if the kernel
122 * was compiled for BE *and* the node has a "native-endian" property.
123 * Returns false otherwise.
125 bool of_fdt_is_big_endian(const void *blob, unsigned long node)
127 if (fdt_getprop(blob, node, "big-endian", NULL))
129 if (IS_ENABLED(CONFIG_CPU_BIG_ENDIAN) &&
130 fdt_getprop(blob, node, "native-endian", NULL))
135 static bool of_fdt_device_is_available(const void *blob, unsigned long node)
137 const char *status = fdt_getprop(blob, node, "status", NULL);
142 if (!strcmp(status, "ok") || !strcmp(status, "okay"))
149 * of_fdt_match - Return true if node matches a list of compatible values
151 int of_fdt_match(const void *blob, unsigned long node,
152 const char *const *compat)
154 unsigned int tmp, score = 0;
160 tmp = of_fdt_is_compatible(blob, node, *compat);
161 if (tmp && (score == 0 || (tmp < score)))
169 static void *unflatten_dt_alloc(void **mem, unsigned long size,
174 *mem = PTR_ALIGN(*mem, align);
181 static void populate_properties(const void *blob,
184 struct device_node *np,
185 const char *nodename,
188 struct property *pp, **pprev = NULL;
190 bool has_name = false;
192 pprev = &np->properties;
193 for (cur = fdt_first_property_offset(blob, offset);
195 cur = fdt_next_property_offset(blob, cur)) {
200 val = fdt_getprop_by_offset(blob, cur, &pname, &sz);
202 pr_warn("Cannot locate property at 0x%x\n", cur);
207 pr_warn("Cannot find property name at 0x%x\n", cur);
211 if (!strcmp(pname, "name"))
214 pp = unflatten_dt_alloc(mem, sizeof(struct property),
215 __alignof__(struct property));
219 /* We accept flattened tree phandles either in
220 * ePAPR-style "phandle" properties, or the
221 * legacy "linux,phandle" properties. If both
222 * appear and have different values, things
223 * will get weird. Don't do that.
225 if (!strcmp(pname, "phandle") ||
226 !strcmp(pname, "linux,phandle")) {
228 np->phandle = be32_to_cpup(val);
231 /* And we process the "ibm,phandle" property
232 * used in pSeries dynamic device tree
235 if (!strcmp(pname, "ibm,phandle"))
236 np->phandle = be32_to_cpup(val);
238 pp->name = (char *)pname;
240 pp->value = (__be32 *)val;
245 /* With version 0x10 we may not have the name property,
246 * recreate it here from the unit name if absent
249 const char *p = nodename, *ps = p, *pa = NULL;
255 else if ((*p) == '/')
263 pp = unflatten_dt_alloc(mem, sizeof(struct property) + len,
264 __alignof__(struct property));
271 memcpy(pp->value, ps, len - 1);
272 ((char *)pp->value)[len - 1] = 0;
273 pr_debug("fixed up name for %s -> %s\n",
274 nodename, (char *)pp->value);
282 static bool populate_node(const void *blob,
285 struct device_node *dad,
286 struct device_node **pnp,
289 struct device_node *np;
291 unsigned int l, allocl;
293 pathp = fdt_get_name(blob, offset, &l);
301 np = unflatten_dt_alloc(mem, sizeof(struct device_node) + allocl,
302 __alignof__(struct device_node));
306 np->full_name = fn = ((char *)np) + sizeof(*np);
308 memcpy(fn, pathp, l);
312 np->sibling = dad->child;
317 populate_properties(blob, offset, mem, np, pathp, dryrun);
319 np->name = of_get_property(np, "name", NULL);
320 np->type = of_get_property(np, "device_type", NULL);
332 static void reverse_nodes(struct device_node *parent)
334 struct device_node *child, *next;
337 child = parent->child;
339 reverse_nodes(child);
341 child = child->sibling;
344 /* Reverse the nodes in the child list */
345 child = parent->child;
346 parent->child = NULL;
348 next = child->sibling;
350 child->sibling = parent->child;
351 parent->child = child;
357 * unflatten_dt_nodes - Alloc and populate a device_node from the flat tree
358 * @blob: The parent device tree blob
359 * @mem: Memory chunk to use for allocating device nodes and properties
360 * @dad: Parent struct device_node
361 * @nodepp: The device_node tree created by the call
363 * It returns the size of unflattened device tree or error code
365 static int unflatten_dt_nodes(const void *blob,
367 struct device_node *dad,
368 struct device_node **nodepp)
370 struct device_node *root;
371 int offset = 0, depth = 0, initial_depth = 0;
372 #define FDT_MAX_DEPTH 64
373 struct device_node *nps[FDT_MAX_DEPTH];
381 * We're unflattening device sub-tree if @dad is valid. There are
382 * possibly multiple nodes in the first level of depth. We need
383 * set @depth to 1 to make fdt_next_node() happy as it bails
384 * immediately when negative @depth is found. Otherwise, the device
385 * nodes except the first one won't be unflattened successfully.
388 depth = initial_depth = 1;
394 offset >= 0 && depth >= initial_depth;
395 offset = fdt_next_node(blob, offset, &depth)) {
396 if (WARN_ON_ONCE(depth >= FDT_MAX_DEPTH))
399 if (!IS_ENABLED(CONFIG_OF_KOBJ) &&
400 !of_fdt_device_is_available(blob, offset))
403 if (!populate_node(blob, offset, &mem, nps[depth],
404 &nps[depth+1], dryrun))
407 if (!dryrun && nodepp && !*nodepp)
408 *nodepp = nps[depth+1];
409 if (!dryrun && !root)
413 if (offset < 0 && offset != -FDT_ERR_NOTFOUND) {
414 pr_err("Error %d processing FDT\n", offset);
419 * Reverse the child list. Some drivers assumes node order matches .dts
429 * __unflatten_device_tree - create tree of device_nodes from flat blob
431 * unflattens a device-tree, creating the
432 * tree of struct device_node. It also fills the "name" and "type"
433 * pointers of the nodes so the normal device-tree walking functions
435 * @blob: The blob to expand
436 * @dad: Parent device node
437 * @mynodes: The device_node tree created by the call
438 * @dt_alloc: An allocator that provides a virtual address to memory
439 * for the resulting tree
440 * @detached: if true set OF_DETACHED on @mynodes
442 * Returns NULL on failure or the memory chunk containing the unflattened
443 * device tree on success.
445 void *__unflatten_device_tree(const void *blob,
446 struct device_node *dad,
447 struct device_node **mynodes,
448 void *(*dt_alloc)(u64 size, u64 align),
454 pr_debug(" -> unflatten_device_tree()\n");
457 pr_debug("No device tree pointer\n");
461 pr_debug("Unflattening device tree:\n");
462 pr_debug("magic: %08x\n", fdt_magic(blob));
463 pr_debug("size: %08x\n", fdt_totalsize(blob));
464 pr_debug("version: %08x\n", fdt_version(blob));
466 if (fdt_check_header(blob)) {
467 pr_err("Invalid device tree blob header\n");
471 /* First pass, scan for size */
472 size = unflatten_dt_nodes(blob, NULL, dad, NULL);
476 size = ALIGN(size, 4);
477 pr_debug(" size is %d, allocating...\n", size);
479 /* Allocate memory for the expanded device tree */
480 mem = dt_alloc(size + 4, __alignof__(struct device_node));
484 memset(mem, 0, size);
486 *(__be32 *)(mem + size) = cpu_to_be32(0xdeadbeef);
488 pr_debug(" unflattening %p...\n", mem);
490 /* Second pass, do actual unflattening */
491 unflatten_dt_nodes(blob, mem, dad, mynodes);
492 if (be32_to_cpup(mem + size) != 0xdeadbeef)
493 pr_warning("End of tree marker overwritten: %08x\n",
494 be32_to_cpup(mem + size));
496 if (detached && mynodes) {
497 of_node_set_flag(*mynodes, OF_DETACHED);
498 pr_debug("unflattened tree is detached\n");
501 pr_debug(" <- unflatten_device_tree()\n");
505 static void *kernel_tree_alloc(u64 size, u64 align)
507 return kzalloc(size, GFP_KERNEL);
510 static DEFINE_MUTEX(of_fdt_unflatten_mutex);
513 * of_fdt_unflatten_tree - create tree of device_nodes from flat blob
514 * @blob: Flat device tree blob
515 * @dad: Parent device node
516 * @mynodes: The device tree created by the call
518 * unflattens the device-tree passed by the firmware, creating the
519 * tree of struct device_node. It also fills the "name" and "type"
520 * pointers of the nodes so the normal device-tree walking functions
523 * Returns NULL on failure or the memory chunk containing the unflattened
524 * device tree on success.
526 void *of_fdt_unflatten_tree(const unsigned long *blob,
527 struct device_node *dad,
528 struct device_node **mynodes)
532 mutex_lock(&of_fdt_unflatten_mutex);
533 mem = __unflatten_device_tree(blob, dad, mynodes, &kernel_tree_alloc,
535 mutex_unlock(&of_fdt_unflatten_mutex);
539 EXPORT_SYMBOL_GPL(of_fdt_unflatten_tree);
541 /* Everything below here references initial_boot_params directly. */
542 int __initdata dt_root_addr_cells;
543 int __initdata dt_root_size_cells;
545 void *initial_boot_params;
547 #ifdef CONFIG_OF_EARLY_FLATTREE
549 static u32 of_fdt_crc32;
552 * res_mem_reserve_reg() - reserve all memory described in 'reg' property
554 static int __init __reserved_mem_reserve_reg(unsigned long node,
557 int t_len = (dt_root_addr_cells + dt_root_size_cells) * sizeof(__be32);
558 phys_addr_t base, size;
561 int nomap, first = 1;
563 prop = of_get_flat_dt_prop(node, "reg", &len);
567 if (len && len % t_len != 0) {
568 pr_err("Reserved memory: invalid reg property in '%s', skipping node.\n",
573 nomap = of_get_flat_dt_prop(node, "no-map", NULL) != NULL;
575 while (len >= t_len) {
576 base = dt_mem_next_cell(dt_root_addr_cells, &prop);
577 size = dt_mem_next_cell(dt_root_size_cells, &prop);
580 early_init_dt_reserve_memory_arch(base, size, nomap) == 0)
581 pr_debug("Reserved memory: reserved region for node '%s': base %pa, size %ld MiB\n",
582 uname, &base, (unsigned long)size / SZ_1M);
584 pr_info("Reserved memory: failed to reserve memory for node '%s': base %pa, size %ld MiB\n",
585 uname, &base, (unsigned long)size / SZ_1M);
589 fdt_reserved_mem_save_node(node, uname, base, size);
597 * __reserved_mem_check_root() - check if #size-cells, #address-cells provided
598 * in /reserved-memory matches the values supported by the current implementation,
599 * also check if ranges property has been provided
601 static int __init __reserved_mem_check_root(unsigned long node)
605 prop = of_get_flat_dt_prop(node, "#size-cells", NULL);
606 if (!prop || be32_to_cpup(prop) != dt_root_size_cells)
609 prop = of_get_flat_dt_prop(node, "#address-cells", NULL);
610 if (!prop || be32_to_cpup(prop) != dt_root_addr_cells)
613 prop = of_get_flat_dt_prop(node, "ranges", NULL);
620 * fdt_scan_reserved_mem() - scan a single FDT node for reserved memory
622 static int __init __fdt_scan_reserved_mem(unsigned long node, const char *uname,
623 int depth, void *data)
628 if (!found && depth == 1 && strcmp(uname, "reserved-memory") == 0) {
629 if (__reserved_mem_check_root(node) != 0) {
630 pr_err("Reserved memory: unsupported node format, ignoring\n");
640 } else if (found && depth < 2) {
641 /* scanning of /reserved-memory has been finished */
645 if (!of_fdt_device_is_available(initial_boot_params, node))
648 err = __reserved_mem_reserve_reg(node, uname);
649 if (err == -ENOENT && of_get_flat_dt_prop(node, "size", NULL))
650 fdt_reserved_mem_save_node(node, uname, 0, 0);
657 * early_init_fdt_scan_reserved_mem() - create reserved memory regions
659 * This function grabs memory from early allocator for device exclusive use
660 * defined in device tree structures. It should be called by arch specific code
661 * once the early allocator (i.e. memblock) has been fully activated.
663 void __init early_init_fdt_scan_reserved_mem(void)
668 if (!initial_boot_params)
671 /* Process header /memreserve/ fields */
673 fdt_get_mem_rsv(initial_boot_params, n, &base, &size);
676 early_init_dt_reserve_memory_arch(base, size, 0);
679 of_scan_flat_dt(__fdt_scan_reserved_mem, NULL);
680 fdt_init_reserved_mem();
684 * early_init_fdt_reserve_self() - reserve the memory used by the FDT blob
686 void __init early_init_fdt_reserve_self(void)
688 if (!initial_boot_params)
691 /* Reserve the dtb region */
692 early_init_dt_reserve_memory_arch(__pa(initial_boot_params),
693 fdt_totalsize(initial_boot_params),
698 * of_scan_flat_dt - scan flattened tree blob and call callback on each.
699 * @it: callback function
700 * @data: context data pointer
702 * This function is used to scan the flattened device-tree, it is
703 * used to extract the memory information at boot before we can
706 int __init of_scan_flat_dt(int (*it)(unsigned long node,
707 const char *uname, int depth,
711 const void *blob = initial_boot_params;
713 int offset, rc = 0, depth = -1;
718 for (offset = fdt_next_node(blob, -1, &depth);
719 offset >= 0 && depth >= 0 && !rc;
720 offset = fdt_next_node(blob, offset, &depth)) {
722 pathp = fdt_get_name(blob, offset, NULL);
724 pathp = kbasename(pathp);
725 rc = it(offset, pathp, depth, data);
731 * of_scan_flat_dt_subnodes - scan sub-nodes of a node call callback on each.
732 * @it: callback function
733 * @data: context data pointer
735 * This function is used to scan sub-nodes of a node.
737 int __init of_scan_flat_dt_subnodes(unsigned long parent,
738 int (*it)(unsigned long node,
743 const void *blob = initial_boot_params;
746 fdt_for_each_subnode(node, blob, parent) {
750 pathp = fdt_get_name(blob, node, NULL);
752 pathp = kbasename(pathp);
753 rc = it(node, pathp, data);
761 * of_get_flat_dt_subnode_by_name - get the subnode by given name
763 * @node: the parent node
764 * @uname: the name of subnode
765 * @return offset of the subnode, or -FDT_ERR_NOTFOUND if there is none
768 int of_get_flat_dt_subnode_by_name(unsigned long node, const char *uname)
770 return fdt_subnode_offset(initial_boot_params, node, uname);
774 * of_get_flat_dt_root - find the root node in the flat blob
776 unsigned long __init of_get_flat_dt_root(void)
782 * of_get_flat_dt_size - Return the total size of the FDT
784 int __init of_get_flat_dt_size(void)
786 return fdt_totalsize(initial_boot_params);
790 * of_get_flat_dt_prop - Given a node in the flat blob, return the property ptr
792 * This function can be used within scan_flattened_dt callback to get
793 * access to properties
795 const void *__init of_get_flat_dt_prop(unsigned long node, const char *name,
798 return fdt_getprop(initial_boot_params, node, name, size);
802 * of_flat_dt_is_compatible - Return true if given node has compat in compatible list
803 * @node: node to test
804 * @compat: compatible string to compare with compatible list.
806 int __init of_flat_dt_is_compatible(unsigned long node, const char *compat)
808 return of_fdt_is_compatible(initial_boot_params, node, compat);
812 * of_flat_dt_match - Return true if node matches a list of compatible values
814 int __init of_flat_dt_match(unsigned long node, const char *const *compat)
816 return of_fdt_match(initial_boot_params, node, compat);
820 * of_get_flat_dt_prop - Given a node in the flat blob, return the phandle
822 uint32_t __init of_get_flat_dt_phandle(unsigned long node)
824 return fdt_get_phandle(initial_boot_params, node);
827 struct fdt_scan_status {
832 int (*iterator)(unsigned long node, const char *uname, int depth, void *data);
836 const char * __init of_flat_dt_get_machine_name(void)
839 unsigned long dt_root = of_get_flat_dt_root();
841 name = of_get_flat_dt_prop(dt_root, "model", NULL);
843 name = of_get_flat_dt_prop(dt_root, "compatible", NULL);
848 * of_flat_dt_match_machine - Iterate match tables to find matching machine.
850 * @default_match: A machine specific ptr to return in case of no match.
851 * @get_next_compat: callback function to return next compatible match table.
853 * Iterate through machine match tables to find the best match for the machine
854 * compatible string in the FDT.
856 const void * __init of_flat_dt_match_machine(const void *default_match,
857 const void * (*get_next_compat)(const char * const**))
859 const void *data = NULL;
860 const void *best_data = default_match;
861 const char *const *compat;
862 unsigned long dt_root;
863 unsigned int best_score = ~1, score = 0;
865 dt_root = of_get_flat_dt_root();
866 while ((data = get_next_compat(&compat))) {
867 score = of_flat_dt_match(dt_root, compat);
868 if (score > 0 && score < best_score) {
877 pr_err("\n unrecognized device tree list:\n[ ");
879 prop = of_get_flat_dt_prop(dt_root, "compatible", &size);
882 printk("'%s' ", prop);
883 size -= strlen(prop) + 1;
884 prop += strlen(prop) + 1;
891 pr_info("Machine model: %s\n", of_flat_dt_get_machine_name());
896 #ifdef CONFIG_BLK_DEV_INITRD
897 #ifndef __early_init_dt_declare_initrd
898 static void __early_init_dt_declare_initrd(unsigned long start,
901 initrd_start = (unsigned long)__va(start);
902 initrd_end = (unsigned long)__va(end);
903 initrd_below_start_ok = 1;
908 * early_init_dt_check_for_initrd - Decode initrd location from flat tree
909 * @node: reference to node containing initrd location ('chosen')
911 static void __init early_init_dt_check_for_initrd(unsigned long node)
917 pr_debug("Looking for initrd properties... ");
919 prop = of_get_flat_dt_prop(node, "linux,initrd-start", &len);
922 start = of_read_number(prop, len/4);
924 prop = of_get_flat_dt_prop(node, "linux,initrd-end", &len);
927 end = of_read_number(prop, len/4);
929 __early_init_dt_declare_initrd(start, end);
931 pr_debug("initrd_start=0x%llx initrd_end=0x%llx\n",
932 (unsigned long long)start, (unsigned long long)end);
935 static inline void early_init_dt_check_for_initrd(unsigned long node)
938 #endif /* CONFIG_BLK_DEV_INITRD */
940 #ifdef CONFIG_SERIAL_EARLYCON
942 int __init early_init_dt_scan_chosen_stdout(void)
945 const char *p, *q, *options = NULL;
947 const struct earlycon_id *match;
948 const void *fdt = initial_boot_params;
950 offset = fdt_path_offset(fdt, "/chosen");
952 offset = fdt_path_offset(fdt, "/chosen@0");
956 p = fdt_getprop(fdt, offset, "stdout-path", &l);
958 p = fdt_getprop(fdt, offset, "linux,stdout-path", &l);
962 q = strchrnul(p, ':');
967 /* Get the node specified by stdout-path */
968 offset = fdt_path_offset_namelen(fdt, p, l);
970 pr_warn("earlycon: stdout-path %.*s not found\n", l, p);
974 for (match = __earlycon_table; match < __earlycon_table_end; match++) {
975 if (!match->compatible[0])
978 if (fdt_node_check_compatible(fdt, offset, match->compatible))
981 of_setup_earlycon(match, offset, options);
989 * early_init_dt_scan_root - fetch the top level address and size cells
991 int __init early_init_dt_scan_root(unsigned long node, const char *uname,
992 int depth, void *data)
999 dt_root_size_cells = OF_ROOT_NODE_SIZE_CELLS_DEFAULT;
1000 dt_root_addr_cells = OF_ROOT_NODE_ADDR_CELLS_DEFAULT;
1002 prop = of_get_flat_dt_prop(node, "#size-cells", NULL);
1004 dt_root_size_cells = be32_to_cpup(prop);
1005 pr_debug("dt_root_size_cells = %x\n", dt_root_size_cells);
1007 prop = of_get_flat_dt_prop(node, "#address-cells", NULL);
1009 dt_root_addr_cells = be32_to_cpup(prop);
1010 pr_debug("dt_root_addr_cells = %x\n", dt_root_addr_cells);
1016 u64 __init dt_mem_next_cell(int s, const __be32 **cellp)
1018 const __be32 *p = *cellp;
1021 return of_read_number(p, s);
1025 * early_init_dt_scan_memory - Look for and parse memory nodes
1027 int __init early_init_dt_scan_memory(unsigned long node, const char *uname,
1028 int depth, void *data)
1030 const char *type = of_get_flat_dt_prop(node, "device_type", NULL);
1031 const __be32 *reg, *endp;
1035 /* We are scanning "memory" nodes only */
1038 * The longtrail doesn't have a device_type on the
1039 * /memory node, so look for the node called /memory@0.
1041 if (!IS_ENABLED(CONFIG_PPC32) || depth != 1 || strcmp(uname, "memory@0") != 0)
1043 } else if (strcmp(type, "memory") != 0)
1046 reg = of_get_flat_dt_prop(node, "linux,usable-memory", &l);
1048 reg = of_get_flat_dt_prop(node, "reg", &l);
1052 endp = reg + (l / sizeof(__be32));
1053 hotpluggable = of_get_flat_dt_prop(node, "hotpluggable", NULL);
1055 pr_debug("memory scan node %s, reg size %d,\n", uname, l);
1057 while ((endp - reg) >= (dt_root_addr_cells + dt_root_size_cells)) {
1060 base = dt_mem_next_cell(dt_root_addr_cells, ®);
1061 size = dt_mem_next_cell(dt_root_size_cells, ®);
1065 pr_debug(" - %llx , %llx\n", (unsigned long long)base,
1066 (unsigned long long)size);
1068 early_init_dt_add_memory_arch(base, size);
1073 if (early_init_dt_mark_hotplug_memory_arch(base, size))
1074 pr_warn("failed to mark hotplug range 0x%llx - 0x%llx\n",
1081 int __init early_init_dt_scan_chosen(unsigned long node, const char *uname,
1082 int depth, void *data)
1087 pr_debug("search \"chosen\", depth: %d, uname: %s\n", depth, uname);
1089 if (depth != 1 || !data ||
1090 (strcmp(uname, "chosen") != 0 && strcmp(uname, "chosen@0") != 0))
1093 early_init_dt_check_for_initrd(node);
1095 /* Retrieve command line */
1096 p = of_get_flat_dt_prop(node, "bootargs", &l);
1097 if (p != NULL && l > 0)
1098 strlcpy(data, p, min((int)l, COMMAND_LINE_SIZE));
1101 * CONFIG_CMDLINE is meant to be a default in case nothing else
1102 * managed to set the command line, unless CONFIG_CMDLINE_FORCE
1103 * is set in which case we override whatever was found earlier.
1105 #ifdef CONFIG_CMDLINE
1106 #if defined(CONFIG_CMDLINE_EXTEND)
1107 strlcat(data, " ", COMMAND_LINE_SIZE);
1108 strlcat(data, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
1109 #elif defined(CONFIG_CMDLINE_FORCE)
1110 strlcpy(data, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
1112 /* No arguments from boot loader, use kernel's cmdl*/
1113 if (!((char *)data)[0])
1114 strlcpy(data, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
1116 #endif /* CONFIG_CMDLINE */
1118 pr_debug("Command line is: %s\n", (char*)data);
1124 #ifdef CONFIG_HAVE_MEMBLOCK
1125 #ifndef MIN_MEMBLOCK_ADDR
1126 #define MIN_MEMBLOCK_ADDR __pa(PAGE_OFFSET)
1128 #ifndef MAX_MEMBLOCK_ADDR
1129 #define MAX_MEMBLOCK_ADDR ((phys_addr_t)~0)
1132 void __init __weak early_init_dt_add_memory_arch(u64 base, u64 size)
1134 const u64 phys_offset = MIN_MEMBLOCK_ADDR;
1136 if (!PAGE_ALIGNED(base)) {
1137 if (size < PAGE_SIZE - (base & ~PAGE_MASK)) {
1138 pr_warn("Ignoring memory block 0x%llx - 0x%llx\n",
1142 size -= PAGE_SIZE - (base & ~PAGE_MASK);
1143 base = PAGE_ALIGN(base);
1147 if (base > MAX_MEMBLOCK_ADDR) {
1148 pr_warning("Ignoring memory block 0x%llx - 0x%llx\n",
1153 if (base + size - 1 > MAX_MEMBLOCK_ADDR) {
1154 pr_warning("Ignoring memory range 0x%llx - 0x%llx\n",
1155 ((u64)MAX_MEMBLOCK_ADDR) + 1, base + size);
1156 size = MAX_MEMBLOCK_ADDR - base + 1;
1159 if (base + size < phys_offset) {
1160 pr_warning("Ignoring memory block 0x%llx - 0x%llx\n",
1164 if (base < phys_offset) {
1165 pr_warning("Ignoring memory range 0x%llx - 0x%llx\n",
1167 size -= phys_offset - base;
1170 memblock_add(base, size);
1173 int __init __weak early_init_dt_mark_hotplug_memory_arch(u64 base, u64 size)
1175 return memblock_mark_hotplug(base, size);
1178 int __init __weak early_init_dt_reserve_memory_arch(phys_addr_t base,
1179 phys_addr_t size, bool nomap)
1182 return memblock_remove(base, size);
1183 return memblock_reserve(base, size);
1187 * called from unflatten_device_tree() to bootstrap devicetree itself
1188 * Architectures can override this definition if memblock isn't used
1190 void * __init __weak early_init_dt_alloc_memory_arch(u64 size, u64 align)
1192 return __va(memblock_alloc(size, align));
1195 void __init __weak early_init_dt_add_memory_arch(u64 base, u64 size)
1200 int __init __weak early_init_dt_mark_hotplug_memory_arch(u64 base, u64 size)
1205 int __init __weak early_init_dt_reserve_memory_arch(phys_addr_t base,
1206 phys_addr_t size, bool nomap)
1208 pr_err("Reserved memory not supported, ignoring range %pa - %pa%s\n",
1209 &base, &size, nomap ? " (nomap)" : "");
1213 void * __init __weak early_init_dt_alloc_memory_arch(u64 size, u64 align)
1220 bool __init early_init_dt_verify(void *params)
1225 /* check device tree validity */
1226 if (fdt_check_header(params))
1229 /* Setup flat device-tree pointer */
1230 initial_boot_params = params;
1231 of_fdt_crc32 = crc32_be(~0, initial_boot_params,
1232 fdt_totalsize(initial_boot_params));
1237 void __init early_init_dt_scan_nodes(void)
1239 /* Retrieve various information from the /chosen node */
1240 of_scan_flat_dt(early_init_dt_scan_chosen, boot_command_line);
1242 /* Initialize {size,address}-cells info */
1243 of_scan_flat_dt(early_init_dt_scan_root, NULL);
1245 /* Setup memory, calling early_init_dt_add_memory_arch */
1246 of_scan_flat_dt(early_init_dt_scan_memory, NULL);
1249 bool __init early_init_dt_scan(void *params)
1253 status = early_init_dt_verify(params);
1257 early_init_dt_scan_nodes();
1262 * unflatten_device_tree - create tree of device_nodes from flat blob
1264 * unflattens the device-tree passed by the firmware, creating the
1265 * tree of struct device_node. It also fills the "name" and "type"
1266 * pointers of the nodes so the normal device-tree walking functions
1269 void __init unflatten_device_tree(void)
1271 __unflatten_device_tree(initial_boot_params, NULL, &of_root,
1272 early_init_dt_alloc_memory_arch, false);
1274 /* Get pointer to "/chosen" and "/aliases" nodes for use everywhere */
1275 of_alias_scan(early_init_dt_alloc_memory_arch);
1277 unittest_unflatten_overlay_base();
1281 * unflatten_and_copy_device_tree - copy and create tree of device_nodes from flat blob
1283 * Copies and unflattens the device-tree passed by the firmware, creating the
1284 * tree of struct device_node. It also fills the "name" and "type"
1285 * pointers of the nodes so the normal device-tree walking functions
1286 * can be used. This should only be used when the FDT memory has not been
1287 * reserved such is the case when the FDT is built-in to the kernel init
1288 * section. If the FDT memory is reserved already then unflatten_device_tree
1289 * should be used instead.
1291 void __init unflatten_and_copy_device_tree(void)
1296 if (!initial_boot_params) {
1297 pr_warn("No valid device tree found, continuing without\n");
1301 size = fdt_totalsize(initial_boot_params);
1302 dt = early_init_dt_alloc_memory_arch(size,
1303 roundup_pow_of_two(FDT_V17_SIZE));
1306 memcpy(dt, initial_boot_params, size);
1307 initial_boot_params = dt;
1309 unflatten_device_tree();
1313 static ssize_t of_fdt_raw_read(struct file *filp, struct kobject *kobj,
1314 struct bin_attribute *bin_attr,
1315 char *buf, loff_t off, size_t count)
1317 memcpy(buf, initial_boot_params + off, count);
1321 static int __init of_fdt_raw_init(void)
1323 static struct bin_attribute of_fdt_raw_attr =
1324 __BIN_ATTR(fdt, S_IRUSR, of_fdt_raw_read, NULL, 0);
1326 if (!initial_boot_params)
1329 if (of_fdt_crc32 != crc32_be(~0, initial_boot_params,
1330 fdt_totalsize(initial_boot_params))) {
1331 pr_warn("not creating '/sys/firmware/fdt': CRC check failed\n");
1334 of_fdt_raw_attr.size = fdt_totalsize(initial_boot_params);
1335 return sysfs_create_bin_file(firmware_kobj, &of_fdt_raw_attr);
1337 late_initcall(of_fdt_raw_init);
1340 #endif /* CONFIG_OF_EARLY_FLATTREE */