xref: /openbmc/qemu/include/sysemu/device_tree.h (revision a68694cd)
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 #ifdef CONFIG_LINUX
20 /**
21  * load_device_tree_from_sysfs: reads the device tree information in the
22  * /proc/device-tree directory and return the corresponding binary blob
23  * buffer pointer. Asserts in case of error.
24  */
25 void *load_device_tree_from_sysfs(void);
26 #endif
27 
28 /**
29  * qemu_fdt_node_path: return the paths of nodes matching a given
30  * name and compat string
31  * @fdt: pointer to the dt blob
32  * @name: node name
33  * @compat: compatibility string
34  * @errp: handle to an error object
35  *
36  * returns a newly allocated NULL-terminated array of node paths.
37  * Use g_strfreev() to free it. If one or more nodes were found, the
38  * array contains the path of each node and the last element equals to
39  * NULL. If there is no error but no matching node was found, the
40  * returned array contains a single element equal to NULL. If an error
41  * was encountered when parsing the blob, the function returns NULL
42  *
43  * @name may be NULL to wildcard names and only match compatibility
44  * strings.
45  */
46 char **qemu_fdt_node_path(void *fdt, const char *name, const char *compat,
47                           Error **errp);
48 
49 /**
50  * qemu_fdt_node_unit_path: return the paths of nodes matching a given
51  * node-name, ie. node-name and node-name@unit-address
52  * @fdt: pointer to the dt blob
53  * @name: node name
54  * @errp: handle to an error object
55  *
56  * returns a newly allocated NULL-terminated array of node paths.
57  * Use g_strfreev() to free it. If one or more nodes were found, the
58  * array contains the path of each node and the last element equals to
59  * NULL. If there is no error but no matching node was found, the
60  * returned array contains a single element equal to NULL. If an error
61  * was encountered when parsing the blob, the function returns NULL
62  */
63 char **qemu_fdt_node_unit_path(void *fdt, const char *name, Error **errp);
64 
65 int qemu_fdt_setprop(void *fdt, const char *node_path,
66                      const char *property, const void *val, int size);
67 int qemu_fdt_setprop_cell(void *fdt, const char *node_path,
68                           const char *property, uint32_t val);
69 int qemu_fdt_setprop_u64(void *fdt, const char *node_path,
70                          const char *property, uint64_t val);
71 int qemu_fdt_setprop_string(void *fdt, const char *node_path,
72                             const char *property, const char *string);
73 int qemu_fdt_setprop_phandle(void *fdt, const char *node_path,
74                              const char *property,
75                              const char *target_node_path);
76 /**
77  * qemu_fdt_getprop: retrieve the value of a given property
78  * @fdt: pointer to the device tree blob
79  * @node_path: node path
80  * @property: name of the property to find
81  * @lenp: fdt error if any or length of the property on success
82  * @errp: handle to an error object
83  *
84  * returns a pointer to the property on success and NULL on failure
85  */
86 const void *qemu_fdt_getprop(void *fdt, const char *node_path,
87                              const char *property, int *lenp,
88                              Error **errp);
89 /**
90  * qemu_fdt_getprop_cell: retrieve the value of a given 4 byte property
91  * @fdt: pointer to the device tree blob
92  * @node_path: node path
93  * @property: name of the property to find
94  * @lenp: fdt error if any or -EINVAL if the property size is different from
95  *        4 bytes, or 4 (expected length of the property) upon success.
96  * @errp: handle to an error object
97  *
98  * returns the property value on success
99  */
100 uint32_t qemu_fdt_getprop_cell(void *fdt, const char *node_path,
101                                const char *property, int *lenp,
102                                Error **errp);
103 uint32_t qemu_fdt_get_phandle(void *fdt, const char *path);
104 uint32_t qemu_fdt_alloc_phandle(void *fdt);
105 int qemu_fdt_nop_node(void *fdt, const char *node_path);
106 int qemu_fdt_add_subnode(void *fdt, const char *name);
107 
108 #define qemu_fdt_setprop_cells(fdt, node_path, property, ...)                 \
109     do {                                                                      \
110         uint32_t qdt_tmp[] = { __VA_ARGS__ };                                 \
111         int i;                                                                \
112                                                                               \
113         for (i = 0; i < ARRAY_SIZE(qdt_tmp); i++) {                           \
114             qdt_tmp[i] = cpu_to_be32(qdt_tmp[i]);                             \
115         }                                                                     \
116         qemu_fdt_setprop(fdt, node_path, property, qdt_tmp,                   \
117                          sizeof(qdt_tmp));                                    \
118     } while (0)
119 
120 void qemu_fdt_dumpdtb(void *fdt, int size);
121 
122 /**
123  * qemu_fdt_setprop_sized_cells_from_array:
124  * @fdt: device tree blob
125  * @node_path: node to set property on
126  * @property: property to set
127  * @numvalues: number of values
128  * @values: array of number-of-cells, value pairs
129  *
130  * Set the specified property on the specified node in the device tree
131  * to be an array of cells. The values of the cells are specified via
132  * the values list, which alternates between "number of cells used by
133  * this value" and "value".
134  * number-of-cells must be either 1 or 2 (other values will result in
135  * an error being returned). If a value is too large to fit in the
136  * number of cells specified for it, an error is returned.
137  *
138  * This function is useful because device tree nodes often have cell arrays
139  * which are either lists of addresses or lists of address,size tuples, but
140  * the number of cells used for each element vary depending on the
141  * #address-cells and #size-cells properties of their parent node.
142  * If you know all your cell elements are one cell wide you can use the
143  * simpler qemu_fdt_setprop_cells(). If you're not setting up the
144  * array programmatically, qemu_fdt_setprop_sized_cells may be more
145  * convenient.
146  *
147  * Return value: 0 on success, <0 on error.
148  */
149 int qemu_fdt_setprop_sized_cells_from_array(void *fdt,
150                                             const char *node_path,
151                                             const char *property,
152                                             int numvalues,
153                                             uint64_t *values);
154 
155 /**
156  * qemu_fdt_setprop_sized_cells:
157  * @fdt: device tree blob
158  * @node_path: node to set property on
159  * @property: property to set
160  * @...: list of number-of-cells, value pairs
161  *
162  * Set the specified property on the specified node in the device tree
163  * to be an array of cells. The values of the cells are specified via
164  * the variable arguments, which alternates between "number of cells
165  * used by this value" and "value".
166  *
167  * This is a convenience wrapper for the function
168  * qemu_fdt_setprop_sized_cells_from_array().
169  *
170  * Return value: 0 on success, <0 on error.
171  */
172 #define qemu_fdt_setprop_sized_cells(fdt, node_path, property, ...)       \
173     ({                                                                    \
174         uint64_t qdt_tmp[] = { __VA_ARGS__ };                             \
175         qemu_fdt_setprop_sized_cells_from_array(fdt, node_path,           \
176                                                 property,                 \
177                                                 ARRAY_SIZE(qdt_tmp) / 2,  \
178                                                 qdt_tmp);                 \
179     })
180 
181 #define FDT_PCI_RANGE_RELOCATABLE          0x80000000
182 #define FDT_PCI_RANGE_PREFETCHABLE         0x40000000
183 #define FDT_PCI_RANGE_ALIASED              0x20000000
184 #define FDT_PCI_RANGE_TYPE_MASK            0x03000000
185 #define FDT_PCI_RANGE_MMIO_64BIT           0x03000000
186 #define FDT_PCI_RANGE_MMIO                 0x02000000
187 #define FDT_PCI_RANGE_IOPORT               0x01000000
188 #define FDT_PCI_RANGE_CONFIG               0x00000000
189 
190 #endif /* DEVICE_TREE_H */
191