xref: /openbmc/linux/include/linux/of_fdt.h (revision b398123b)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  * Definitions 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 #ifndef _LINUX_OF_FDT_H
10 #define _LINUX_OF_FDT_H
11 
12 #include <linux/types.h>
13 #include <linux/init.h>
14 #include <linux/errno.h>
15 
16 /* Definitions used by the flattened device tree */
17 #define OF_DT_HEADER		0xd00dfeed	/* marker */
18 
19 #ifndef __ASSEMBLY__
20 
21 #if defined(CONFIG_OF_FLATTREE)
22 
23 struct device_node;
24 
25 /* For scanning an arbitrary device-tree at any time */
26 extern void *of_fdt_unflatten_tree(const unsigned long *blob,
27 				   struct device_node *dad,
28 				   struct device_node **mynodes);
29 
30 /* TBD: Temporary export of fdt globals - remove when code fully merged */
31 extern int __initdata dt_root_addr_cells;
32 extern int __initdata dt_root_size_cells;
33 extern void *initial_boot_params;
34 
35 extern char __dtb_start[];
36 extern char __dtb_end[];
37 
38 /* Other Prototypes */
39 extern u64 of_flat_dt_translate_address(unsigned long node);
40 extern void of_fdt_limit_memory(int limit);
41 #endif /* CONFIG_OF_FLATTREE */
42 
43 #ifdef CONFIG_OF_EARLY_FLATTREE
44 /* For scanning the flat device-tree at boot time */
45 extern int of_scan_flat_dt(int (*it)(unsigned long node, const char *uname,
46 				     int depth, void *data),
47 			   void *data);
48 extern int of_scan_flat_dt_subnodes(unsigned long node,
49 				    int (*it)(unsigned long node,
50 					      const char *uname,
51 					      void *data),
52 				    void *data);
53 extern int of_get_flat_dt_subnode_by_name(unsigned long node,
54 					  const char *uname);
55 extern const void *of_get_flat_dt_prop(unsigned long node, const char *name,
56 				       int *size);
57 extern int of_flat_dt_is_compatible(unsigned long node, const char *name);
58 extern unsigned long of_get_flat_dt_root(void);
59 extern uint32_t of_get_flat_dt_phandle(unsigned long node);
60 
61 extern int early_init_dt_scan_chosen(char *cmdline);
62 extern int early_init_dt_scan_memory(void);
63 extern void early_init_dt_check_for_usable_mem_range(void);
64 extern int early_init_dt_scan_chosen_stdout(void);
65 extern void early_init_fdt_scan_reserved_mem(void);
66 extern void early_init_fdt_reserve_self(void);
67 extern void early_init_dt_add_memory_arch(u64 base, u64 size);
68 extern u64 dt_mem_next_cell(int s, const __be32 **cellp);
69 
70 /* Early flat tree scan hooks */
71 extern int early_init_dt_scan_root(void);
72 
73 extern bool early_init_dt_scan(void *params);
74 extern bool early_init_dt_verify(void *params);
75 extern void early_init_dt_scan_nodes(void);
76 
77 extern const char *of_flat_dt_get_machine_name(void);
78 extern const void *of_flat_dt_match_machine(const void *default_match,
79 		const void * (*get_next_compat)(const char * const**));
80 
81 /* Other Prototypes */
82 extern void unflatten_device_tree(void);
83 extern void unflatten_and_copy_device_tree(void);
84 extern void early_init_devtree(void *);
85 extern void early_get_first_memblock_info(void *, phys_addr_t *);
86 #else /* CONFIG_OF_EARLY_FLATTREE */
early_init_dt_check_for_usable_mem_range(void)87 static inline void early_init_dt_check_for_usable_mem_range(void) {}
early_init_dt_scan_chosen_stdout(void)88 static inline int early_init_dt_scan_chosen_stdout(void) { return -ENODEV; }
early_init_fdt_scan_reserved_mem(void)89 static inline void early_init_fdt_scan_reserved_mem(void) {}
early_init_fdt_reserve_self(void)90 static inline void early_init_fdt_reserve_self(void) {}
of_flat_dt_get_machine_name(void)91 static inline const char *of_flat_dt_get_machine_name(void) { return NULL; }
unflatten_device_tree(void)92 static inline void unflatten_device_tree(void) {}
unflatten_and_copy_device_tree(void)93 static inline void unflatten_and_copy_device_tree(void) {}
94 #endif /* CONFIG_OF_EARLY_FLATTREE */
95 
96 #endif /* __ASSEMBLY__ */
97 #endif /* _LINUX_OF_FDT_H */
98