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 */ 87 static inline void early_init_dt_check_for_usable_mem_range(void) {} 88 static inline int early_init_dt_scan_chosen_stdout(void) { return -ENODEV; } 89 static inline void early_init_fdt_scan_reserved_mem(void) {} 90 static inline void early_init_fdt_reserve_self(void) {} 91 static inline const char *of_flat_dt_get_machine_name(void) { return NULL; } 92 static inline void unflatten_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