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 char *of_fdt_get_string(const void *blob, u32 offset); 27 extern void *of_fdt_get_property(const void *blob, 28 unsigned long node, 29 const char *name, 30 int *size); 31 extern bool of_fdt_is_big_endian(const void *blob, 32 unsigned long node); 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); 38 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; 43 44 extern char __dtb_start[]; 45 extern char __dtb_end[]; 46 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 */ 51 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), 56 void *data); 57 extern int of_scan_flat_dt_subnodes(unsigned long node, 58 int (*it)(unsigned long node, 59 const char *uname, 60 void *data), 61 void *data); 62 extern int of_get_flat_dt_subnode_by_name(unsigned long node, 63 const char *uname); 64 extern const void *of_get_flat_dt_prop(unsigned long node, const char *name, 65 int *size); 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); 71 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, 82 bool no_map); 83 extern u64 dt_mem_next_cell(int s, const __be32 **cellp); 84 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); 88 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); 92 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**)); 96 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 */ 110 111 #endif /* __ASSEMBLY__ */ 112 #endif /* _LINUX_OF_FDT_H */ 113