include/linux/of_fdt.h

0001 /* SPDX-License-Identifier: GPL-2.0 */
0002 /*
0003  * Definitions for working with the Flattened Device Tree data format
0004  *
0005  * Copyright 2009 Benjamin Herrenschmidt, IBM Corp
0006  * benh@kernel.crashing.org
0007  */
0008
0009 #ifndef _LINUX_OF_FDT_H
0010 #define _LINUX_OF_FDT_H
0011
0012 #include <linux/types.h>
0013 #include <linux/init.h>
0014 #include <linux/errno.h>
0015
0016 /* Definitions used by the flattened device tree */
0017 #define OF_DT_HEADER        0xd00dfeed  /* marker */
0018
0019 #ifndef __ASSEMBLY__
0020
0021 #if defined(CONFIG_OF_FLATTREE)
0022
0023 struct device_node;
0024
0025 /* For scanning an arbitrary device-tree at any time */
0026 extern void *of_fdt_unflatten_tree(const unsigned long *blob,
0027                    struct device_node *dad,
0028                    struct device_node **mynodes);
0029
0030 /* TBD: Temporary export of fdt globals - remove when code fully merged */
0031 extern int __initdata dt_root_addr_cells;
0032 extern int __initdata dt_root_size_cells;
0033 extern void *initial_boot_params;
0034
0035 extern char __dtb_start[];
0036 extern char __dtb_end[];
0037
0038 /* Other Prototypes */
0039 extern u64 of_flat_dt_translate_address(unsigned long node);
0040 extern void of_fdt_limit_memory(int limit);
0041 #endif /* CONFIG_OF_FLATTREE */
0042
0043 #ifdef CONFIG_OF_EARLY_FLATTREE
0044 /* For scanning the flat device-tree at boot time */
0045 extern int of_scan_flat_dt(int (*it)(unsigned long node, const char *uname,
0046                      int depth, void *data),
0047                void *data);
0048 extern int of_scan_flat_dt_subnodes(unsigned long node,
0049                     int (*it)(unsigned long node,
0050                           const char *uname,
0051                           void *data),
0052                     void *data);
0053 extern int of_get_flat_dt_subnode_by_name(unsigned long node,
0054                       const char *uname);
0055 extern const void *of_get_flat_dt_prop(unsigned long node, const char *name,
0056                        int *size);
0057 extern int of_flat_dt_is_compatible(unsigned long node, const char *name);
0058 extern unsigned long of_get_flat_dt_root(void);
0059 extern uint32_t of_get_flat_dt_phandle(unsigned long node);
0060
0061 extern int early_init_dt_scan_chosen(char *cmdline);
0062 extern int early_init_dt_scan_memory(void);
0063 extern void early_init_dt_check_for_usable_mem_range(void);
0064 extern int early_init_dt_scan_chosen_stdout(void);
0065 extern void early_init_fdt_scan_reserved_mem(void);
0066 extern void early_init_fdt_reserve_self(void);
0067 extern void early_init_dt_add_memory_arch(u64 base, u64 size);
0068 extern u64 dt_mem_next_cell(int s, const __be32 **cellp);
0069
0070 /* Early flat tree scan hooks */
0071 extern int early_init_dt_scan_root(void);
0072
0073 extern bool early_init_dt_scan(void *params);
0074 extern bool early_init_dt_verify(void *params);
0075 extern void early_init_dt_scan_nodes(void);
0076
0077 extern const char *of_flat_dt_get_machine_name(void);
0078 extern const void *of_flat_dt_match_machine(const void *default_match,
0079         const void * (*get_next_compat)(const char * const**));
0080
0081 /* Other Prototypes */
0082 extern void unflatten_device_tree(void);
0083 extern void unflatten_and_copy_device_tree(void);
0084 extern void early_init_devtree(void *);
0085 extern void early_get_first_memblock_info(void *, phys_addr_t *);
0086 #else /* CONFIG_OF_EARLY_FLATTREE */
0087 static inline void early_init_dt_check_for_usable_mem_range(void) {}
0088 static inline int early_init_dt_scan_chosen_stdout(void) { return -ENODEV; }
0089 static inline void early_init_fdt_scan_reserved_mem(void) {}
0090 static inline void early_init_fdt_reserve_self(void) {}
0091 static inline const char *of_flat_dt_get_machine_name(void) { return NULL; }
0092 static inline void unflatten_device_tree(void) {}
0093 static inline void unflatten_and_copy_device_tree(void) {}
0094 #endif /* CONFIG_OF_EARLY_FLATTREE */
0095
0096 #endif /* __ASSEMBLY__ */
0097 #endif /* _LINUX_OF_FDT_H */