1 /* SPDX-License-Identifier: GPL-2.0+ */
2 /*
3  * Copyright (c) 2017 Google, Inc
4  * Written by Simon Glass <sjg@chromium.org>
5  */
6 
7 #ifndef _DM_OF_H
8 #define _DM_OF_H
9 
10 #include <asm/u-boot.h>
11 #include <asm/global_data.h>
12 
13 /* integer value within a device tree property which references another node */
14 typedef u32 phandle;
15 
16 /**
17  * struct property: Device tree property
18  *
19  * @name: Property name
20  * @length: Length of property in bytes
21  * @value: Pointer to property value
22  * @next: Pointer to next property, or NULL if none
23  */
24 struct property {
25 	char *name;
26 	int length;
27 	void *value;
28 	struct property *next;
29 };
30 
31 /**
32  * struct device_node: Device tree node
33  *
34  * @name: Node name
35  * @type: Node type (value of device_type property) or "<NULL>" if none
36  * @phandle: Phandle value of this none, or 0 if none
37  * @full_name: Full path to node, e.g. "/bus@1/spi@1100"
38  * @properties: Pointer to head of list of properties, or NULL if none
39  * @parent: Pointer to parent node, or NULL if this is the root node
40  * @child: Pointer to head of child node list, or NULL if no children
41  * @sibling: Pointer to the next sibling node, or NULL if this is the last
42  */
43 struct device_node {
44 	const char *name;
45 	const char *type;
46 	phandle phandle;
47 	const char *full_name;
48 
49 	struct property *properties;
50 	struct device_node *parent;
51 	struct device_node *child;
52 	struct device_node *sibling;
53 };
54 
55 #define OF_MAX_PHANDLE_ARGS 16
56 
57 /**
58  * struct of_phandle_args - structure to hold phandle and arguments
59  *
60  * This is used when decoding a phandle in a device tree property. Typically
61  * these look like this:
62  *
63  * wibble {
64  *    phandle = <5>;
65  * };
66  *
67  * ...
68  * some-prop = <&wibble 1 2 3>
69  *
70  * Here &node is the phandle of the node 'wibble', i.e. 5. There are three
71  * arguments: 1, 2, 3.
72  *
73  * So when decoding the phandle in some-prop, np will point to wibble,
74  * args_count will be 3 and the three arguments will be in args.
75  *
76  * @np: Node that the phandle refers to
77  * @args_count: Number of arguments
78  * @args: Argument values
79  */
80 struct of_phandle_args {
81 	struct device_node *np;
82 	int args_count;
83 	uint32_t args[OF_MAX_PHANDLE_ARGS];
84 };
85 
86 DECLARE_GLOBAL_DATA_PTR;
87 
88 /**
89  * of_live_active() - check if livetree is active
90  *
91  * @returns true if livetree is active, false it not
92  */
of_live_active(void)93 static inline bool of_live_active(void)
94 {
95 	return gd_of_root() != NULL;
96 }
97 
98 #define OF_BAD_ADDR	((u64)-1)
99 
of_node_full_name(const struct device_node * np)100 static inline const char *of_node_full_name(const struct device_node *np)
101 {
102 	return np ? np->full_name : "<no-node>";
103 }
104 
105 /* Default #address and #size cells */
106 #if !defined(OF_ROOT_NODE_ADDR_CELLS_DEFAULT)
107 #define OF_ROOT_NODE_ADDR_CELLS_DEFAULT 2
108 #define OF_ROOT_NODE_SIZE_CELLS_DEFAULT 1
109 #endif
110 
111 /* Default string compare functions */
112 #if !defined(of_compat_cmp)
113 #define of_compat_cmp(s1, s2, l)	strcasecmp((s1), (s2))
114 #define of_prop_cmp(s1, s2)		strcmp((s1), (s2))
115 #define of_node_cmp(s1, s2)		strcasecmp((s1), (s2))
116 #endif
117 
118 /* Helper to read a big number; size is in cells (not bytes) */
of_read_number(const __be32 * cell,int size)119 static inline u64 of_read_number(const __be32 *cell, int size)
120 {
121 	u64 r = 0;
122 	while (size--)
123 		r = (r << 32) | be32_to_cpu(*(cell++));
124 	return r;
125 }
126 
127 /* Like of_read_number, but we want an unsigned long result */
of_read_ulong(const __be32 * cell,int size)128 static inline unsigned long of_read_ulong(const __be32 *cell, int size)
129 {
130 	/* toss away upper bits if unsigned long is smaller than u64 */
131 	return of_read_number(cell, size);
132 }
133 
134 #endif
135