1 /*
2  * Copyright (c) 2018-2022, ARM Limited and Contributors. All rights reserved.
3  *
4  * SPDX-License-Identifier: BSD-3-Clause
5  */
6 
7 /* Helper functions to offer easier navigation of Device Tree Blob */
8 
9 #ifndef FDT_WRAPPERS_H
10 #define FDT_WRAPPERS_H
11 
12 #include <libfdt_env.h>
13 
14 /* Number of cells, given total length in bytes. Each cell is 4 bytes long */
15 #define NCELLS(len) ((len) / 4U)
16 
17 int fdt_read_uint32(const void *dtb, int node, const char *prop_name,
18 		    uint32_t *value);
19 uint32_t fdt_read_uint32_default(const void *dtb, int node,
20 				 const char *prop_name, uint32_t dflt_value);
21 int fdt_read_uint64(const void *dtb, int node, const char *prop_name,
22 		    uint64_t *value);
23 int fdt_read_uint32_array(const void *dtb, int node, const char *prop_name,
24 			  unsigned int cells, uint32_t *value);
25 int fdtw_read_string(const void *dtb, int node, const char *prop,
26 		char *str, size_t size);
27 int fdtw_read_uuid(const void *dtb, int node, const char *prop,
28 		   unsigned int length, uint8_t *uuid);
29 int fdtw_write_inplace_cells(void *dtb, int node, const char *prop,
30 		unsigned int cells, void *value);
31 int fdtw_read_bytes(const void *dtb, int node, const char *prop,
32 		unsigned int length, void *value);
33 int fdtw_write_inplace_bytes(void *dtb, int node, const char *prop,
34 		unsigned int length, const void *data);
35 int fdt_get_reg_props_by_index(const void *dtb, int node, int index,
36 			       uintptr_t *base, size_t *size);
37 int fdt_get_reg_props_by_name(const void *dtb, int node, const char *name,
38 			      uintptr_t *base, size_t *size);
39 int fdt_get_stdout_node_offset(const void *dtb);
40 
41 uint64_t fdtw_translate_address(const void *dtb, int bus_node,
42 				uint64_t base_address);
43 
44 int fdtw_for_each_cpu(const void *fdt,
45 		      int (*callback)(const void *dtb, int node, uintptr_t mpidr));
46 
47 int fdtw_find_or_add_subnode(void *fdt, int parentoffset, const char *name);
48 
fdt_blob_size(const void * dtb)49 static inline uint32_t fdt_blob_size(const void *dtb)
50 {
51 	const uint32_t *dtb_header = dtb;
52 
53 	return fdt32_to_cpu(dtb_header[1]);
54 }
55 
56 #define fdt_for_each_compatible_node(dtb, node, compatible_str)       \
57 for (node = fdt_node_offset_by_compatible(dtb, -1, compatible_str);   \
58      node >= 0;                                                       \
59      node = fdt_node_offset_by_compatible(dtb, node, compatible_str))
60 
61 #endif /* FDT_WRAPPERS_H */
62