xref: /openbmc/u-boot/include/dm/of.h (revision e625881a)
1 /*
2  * Copyright (c) 2017 Google, Inc
3  * Written by Simon Glass <sjg@chromium.org>
4  *
5  * SPDX-License-Identifier:	GPL-2.0+
6  */
7 
8 #ifndef _DM_OF_H
9 #define _DM_OF_H
10 
11 #include <asm/u-boot.h>
12 #include <asm/global_data.h>
13 
14 /* integer value within a device tree property which references another node */
15 typedef u32 phandle;
16 
17 /**
18  * struct property: Device tree property
19  *
20  * @name: Property name
21  * @length: Length of property in bytes
22  * @value: Pointer to property value
23  * @next: Pointer to next property, or NULL if none
24  */
25 struct property {
26 	char *name;
27 	int length;
28 	void *value;
29 	struct property *next;
30 };
31 
32 /**
33  * struct device_node: Device tree node
34  *
35  * @name: Node name
36  * @type: Node type (value of device_type property) or "<NULL>" if none
37  * @phandle: Phandle value of this none, or 0 if none
38  * @full_name: Full path to node, e.g. "/bus@1/spi@1100"
39  * @properties: Pointer to head of list of properties, or NULL if none
40  * @parent: Pointer to parent node, or NULL if this is the root node
41  * @child: Pointer to head of child node list, or NULL if no children
42  * @sibling: Pointer to the next sibling node, or NULL if this is the last
43  */
44 struct device_node {
45 	const char *name;
46 	const char *type;
47 	phandle phandle;
48 	const char *full_name;
49 
50 	struct property *properties;
51 	struct device_node *parent;
52 	struct device_node *child;
53 	struct device_node *sibling;
54 };
55 
56 #define OF_MAX_PHANDLE_ARGS 16
57 
58 /**
59  * struct of_phandle_args - structure to hold phandle and arguments
60  *
61  * This is used when decoding a phandle in a device tree property. Typically
62  * these look like this:
63  *
64  * wibble {
65  *    phandle = <5>;
66  * };
67  *
68  * ...
69  * some-prop = <&wibble 1 2 3>
70  *
71  * Here &node is the phandle of the node 'wibble', i.e. 5. There are three
72  * arguments: 1, 2, 3.
73  *
74  * So when decoding the phandle in some-prop, np will point to wibble,
75  * args_count will be 3 and the three arguments will be in args.
76  *
77  * @np: Node that the phandle refers to
78  * @args_count: Number of arguments
79  * @args: Argument values
80  */
81 struct of_phandle_args {
82 	struct device_node *np;
83 	int args_count;
84 	uint32_t args[OF_MAX_PHANDLE_ARGS];
85 };
86 
87 DECLARE_GLOBAL_DATA_PTR;
88 
89 /**
90  * of_live_active() - check if livetree is active
91  *
92  * @returns true if livetree is active, false it not
93  */
94 #ifdef CONFIG_OF_LIVE
95 static inline bool of_live_active(void)
96 {
97 	return gd->of_root != NULL;
98 }
99 #else
100 static inline bool of_live_active(void)
101 {
102 	return false;
103 }
104 #endif
105 
106 #define OF_BAD_ADDR	((u64)-1)
107 
108 static inline const char *of_node_full_name(const struct device_node *np)
109 {
110 	return np ? np->full_name : "<no-node>";
111 }
112 
113 /* Default #address and #size cells */
114 #if !defined(OF_ROOT_NODE_ADDR_CELLS_DEFAULT)
115 #define OF_ROOT_NODE_ADDR_CELLS_DEFAULT 1
116 #define OF_ROOT_NODE_SIZE_CELLS_DEFAULT 1
117 #endif
118 
119 /* Default string compare functions */
120 #if !defined(of_compat_cmp)
121 #define of_compat_cmp(s1, s2, l)	strcasecmp((s1), (s2))
122 #define of_prop_cmp(s1, s2)		strcmp((s1), (s2))
123 #define of_node_cmp(s1, s2)		strcasecmp((s1), (s2))
124 #endif
125 
126 /* Helper to read a big number; size is in cells (not bytes) */
127 static inline u64 of_read_number(const __be32 *cell, int size)
128 {
129 	u64 r = 0;
130 	while (size--)
131 		r = (r << 32) | be32_to_cpu(*(cell++));
132 	return r;
133 }
134 
135 /* Like of_read_number, but we want an unsigned long result */
136 static inline unsigned long of_read_ulong(const __be32 *cell, int size)
137 {
138 	/* toss away upper bits if unsigned long is smaller than u64 */
139 	return of_read_number(cell, size);
140 }
141 
142 #endif
143