xref: /openbmc/qemu/include/sysemu/device_tree.h (revision 5b24c641)
1 /*
2  * Header with function prototypes to help device tree manipulation using
3  * libfdt. It also provides functions to read entries from device tree proc
4  * interface.
5  *
6  * Copyright 2008 IBM Corporation.
7  * Authors: Jerone Young <jyoung5@us.ibm.com>
8  *          Hollis Blanchard <hollisb@us.ibm.com>
9  *
10  * This work is licensed under the GNU GPL license version 2 or later.
11  *
12  */
13 
14 #ifndef __DEVICE_TREE_H__
15 #define __DEVICE_TREE_H__
16 
17 void *create_device_tree(int *sizep);
18 void *load_device_tree(const char *filename_path, int *sizep);
19 
20 int qemu_devtree_setprop(void *fdt, const char *node_path,
21                          const char *property, const void *val_array, int size);
22 int qemu_devtree_setprop_cell(void *fdt, const char *node_path,
23                               const char *property, uint32_t val);
24 int qemu_devtree_setprop_u64(void *fdt, const char *node_path,
25                              const char *property, uint64_t val);
26 int qemu_devtree_setprop_string(void *fdt, const char *node_path,
27                                 const char *property, const char *string);
28 int qemu_devtree_setprop_phandle(void *fdt, const char *node_path,
29                                  const char *property,
30                                  const char *target_node_path);
31 const void *qemu_devtree_getprop(void *fdt, const char *node_path,
32                                  const char *property, int *lenp);
33 uint32_t qemu_devtree_getprop_cell(void *fdt, const char *node_path,
34                                    const char *property);
35 uint32_t qemu_devtree_get_phandle(void *fdt, const char *path);
36 uint32_t qemu_devtree_alloc_phandle(void *fdt);
37 int qemu_devtree_nop_node(void *fdt, const char *node_path);
38 int qemu_devtree_add_subnode(void *fdt, const char *name);
39 
40 #define qemu_devtree_setprop_cells(fdt, node_path, property, ...)             \
41     do {                                                                      \
42         uint32_t qdt_tmp[] = { __VA_ARGS__ };                                 \
43         int i;                                                                \
44                                                                               \
45         for (i = 0; i < ARRAY_SIZE(qdt_tmp); i++) {                           \
46             qdt_tmp[i] = cpu_to_be32(qdt_tmp[i]);                             \
47         }                                                                     \
48         qemu_devtree_setprop(fdt, node_path, property, qdt_tmp,               \
49                              sizeof(qdt_tmp));                                \
50     } while (0)
51 
52 void qemu_devtree_dumpdtb(void *fdt, int size);
53 
54 /**
55  * qemu_devtree_setprop_sized_cells_from_array:
56  * @fdt: device tree blob
57  * @node_path: node to set property on
58  * @property: property to set
59  * @numvalues: number of values
60  * @values: array of number-of-cells, value pairs
61  *
62  * Set the specified property on the specified node in the device tree
63  * to be an array of cells. The values of the cells are specified via
64  * the values list, which alternates between "number of cells used by
65  * this value" and "value".
66  * number-of-cells must be either 1 or 2 (other values will result in
67  * an error being returned). If a value is too large to fit in the
68  * number of cells specified for it, an error is returned.
69  *
70  * This function is useful because device tree nodes often have cell arrays
71  * which are either lists of addresses or lists of address,size tuples, but
72  * the number of cells used for each element vary depending on the
73  * #address-cells and #size-cells properties of their parent node.
74  * If you know all your cell elements are one cell wide you can use the
75  * simpler qemu_devtree_setprop_cells(). If you're not setting up the
76  * array programmatically, qemu_devtree_setprop_sized_cells may be more
77  * convenient.
78  *
79  * Return value: 0 on success, <0 on error.
80  */
81 int qemu_devtree_setprop_sized_cells_from_array(void *fdt,
82                                                 const char *node_path,
83                                                 const char *property,
84                                                 int numvalues,
85                                                 uint64_t *values);
86 
87 /**
88  * qemu_devtree_setprop_sized_cells:
89  * @fdt: device tree blob
90  * @node_path: node to set property on
91  * @property: property to set
92  * @...: list of number-of-cells, value pairs
93  *
94  * Set the specified property on the specified node in the device tree
95  * to be an array of cells. The values of the cells are specified via
96  * the variable arguments, which alternates between "number of cells
97  * used by this value" and "value".
98  *
99  * This is a convenience wrapper for the function
100  * qemu_devtree_setprop_sized_cells_from_array().
101  *
102  * Return value: 0 on success, <0 on error.
103  */
104 #define qemu_devtree_setprop_sized_cells(fdt, node_path, property, ...)       \
105     ({                                                                        \
106         uint64_t qdt_tmp[] = { __VA_ARGS__ };                                 \
107         qemu_devtree_setprop_sized_cells_from_array(fdt, node_path,           \
108                                                     property,                 \
109                                                     ARRAY_SIZE(qdt_tmp) / 2,  \
110                                                     qdt_tmp);                 \
111     })
112 
113 #endif /* __DEVICE_TREE_H__ */
114