1 /* SPDX-License-Identifier: GPL-2.0 */
3 * Definitions for working with the Flattened Device Tree data format
5 * Copyright 2009 Benjamin Herrenschmidt, IBM Corp
6 * benh@kernel.crashing.org
9 #ifndef _LINUX_OF_FDT_H
10 #define _LINUX_OF_FDT_H
12 #include <linux/types.h>
13 #include <linux/init.h>
14 #include <linux/errno.h>
16 /* Definitions used by the flattened device tree */
17 #define OF_DT_HEADER 0xd00dfeed /* marker */
21 #if defined(CONFIG_OF_FLATTREE)
25 /* For scanning an arbitrary device-tree at any time */
26 extern char *of_fdt_get_string(const void *blob, u32 offset);
27 extern void *of_fdt_get_property(const void *blob,
31 extern bool of_fdt_is_big_endian(const void *blob,
33 extern int of_fdt_match(const void *blob, unsigned long node,
34 const char *const *compat);
35 extern void *of_fdt_unflatten_tree(const unsigned long *blob,
36 struct device_node *dad,
37 struct device_node **mynodes);
39 /* TBD: Temporary export of fdt globals - remove when code fully merged */
40 extern int __initdata dt_root_addr_cells;
41 extern int __initdata dt_root_size_cells;
42 extern void *initial_boot_params;
44 extern char __dtb_start[];
45 extern char __dtb_end[];
47 /* Other Prototypes */
48 extern u64 of_flat_dt_translate_address(unsigned long node);
49 extern void of_fdt_limit_memory(int limit);
50 #endif /* CONFIG_OF_FLATTREE */
52 #ifdef CONFIG_OF_EARLY_FLATTREE
53 /* For scanning the flat device-tree at boot time */
54 extern int of_scan_flat_dt(int (*it)(unsigned long node, const char *uname,
55 int depth, void *data),
57 extern int of_scan_flat_dt_subnodes(unsigned long node,
58 int (*it)(unsigned long node,
62 extern int of_get_flat_dt_subnode_by_name(unsigned long node,
64 extern const void *of_get_flat_dt_prop(unsigned long node, const char *name,
66 extern int of_flat_dt_is_compatible(unsigned long node, const char *name);
67 extern int of_flat_dt_match(unsigned long node, const char *const *matches);
68 extern unsigned long of_get_flat_dt_root(void);
69 extern int of_get_flat_dt_size(void);
70 extern uint32_t of_get_flat_dt_phandle(unsigned long node);
72 extern int early_init_dt_scan_chosen(unsigned long node, const char *uname,
73 int depth, void *data);
74 extern int early_init_dt_scan_memory(unsigned long node, const char *uname,
75 int depth, void *data);
76 extern int early_init_dt_scan_chosen_stdout(void);
77 extern void early_init_fdt_scan_reserved_mem(void);
78 extern void early_init_fdt_reserve_self(void);
79 extern void early_init_dt_add_memory_arch(u64 base, u64 size);
80 extern int early_init_dt_mark_hotplug_memory_arch(u64 base, u64 size);
81 extern int early_init_dt_reserve_memory_arch(phys_addr_t base, phys_addr_t size,
83 extern u64 dt_mem_next_cell(int s, const __be32 **cellp);
85 /* Early flat tree scan hooks */
86 extern int early_init_dt_scan_root(unsigned long node, const char *uname,
87 int depth, void *data);
89 extern bool early_init_dt_scan(void *params);
90 extern bool early_init_dt_verify(void *params);
91 extern void early_init_dt_scan_nodes(void);
93 extern const char *of_flat_dt_get_machine_name(void);
94 extern const void *of_flat_dt_match_machine(const void *default_match,
95 const void * (*get_next_compat)(const char * const**));
97 /* Other Prototypes */
98 extern void unflatten_device_tree(void);
99 extern void unflatten_and_copy_device_tree(void);
100 extern void early_init_devtree(void *);
101 extern void early_get_first_memblock_info(void *, phys_addr_t *);
102 #else /* CONFIG_OF_EARLY_FLATTREE */
103 static inline int early_init_dt_scan_chosen_stdout(void) { return -ENODEV; }
104 static inline void early_init_fdt_scan_reserved_mem(void) {}
105 static inline void early_init_fdt_reserve_self(void) {}
106 static inline const char *of_flat_dt_get_machine_name(void) { return NULL; }
107 static inline void unflatten_device_tree(void) {}
108 static inline void unflatten_and_copy_device_tree(void) {}
109 #endif /* CONFIG_OF_EARLY_FLATTREE */
111 #endif /* __ASSEMBLY__ */
112 #endif /* _LINUX_OF_FDT_H */